Power5 with hyperthreading [Archive]

strider42

Feb 25, 2003, 02:04 PM

Originally posted by jethroted
While I think the 970 is the most probable next step for apple, they could have been doing some R&D on the power 5 with IBM all this time, and the power 5 could be the next big thing for apple. I know this is a long shot, but apple has to pull a magic rabbit out of their hat to push through the next couple of years. They need to make a huge leap to separate themselves away from the x86 market, and push full force into the pro market again.

*closes eyes and keeps praying*

the power5 is a server chip, the sucessor to the power4. you wouldn't want it in a desktop at all. server chips prioritize things like reliability, not performance. this is evidenced by the fact that the 970 will outperform the power4 in some areas precisely because it doesn't need to worry about a lot of stuff.

There is absolutely 0 chance the power5 will have anything to with apple, ever (unless apple gets into the high end server business, whcih is doubtful).

It is likely (assuming the sucess of the 970) that a power5 derivitice chip will follow, but it doesn't make much sense for that to be anytime soon. The 970 doesn't even exist yet, nor does the power5. So its predecessor and the chip it would be based on are both nonexistent at this point, making it pretty unlikely such a chip would appear, don't you think.

The 970 will be the chip you want, assuming it will scale to high speeds well (and there is nothing to suggest it wouldn't)

spinner

Feb 25, 2003, 03:17 PM

Originally posted by e-coli
I didn't know the P4 had hyperthreading. We need a new chip soon. The G4 is so sorely outdated.

Only the 3.06GHz P4 and later have Hyperthreading technology. Code must be specifically written to take advantage of it, and so far the only software I know that takes advantage of it is Windows XP. There could be others but I am not aware of any.

sparkleytone

Feb 25, 2003, 04:33 PM

MrMacMan

Feb 25, 2003, 05:41 PM

wdlove

Feb 25, 2003, 06:34 PM

I was enthusiastic after reading the article. Now I'm depressed, is there any hope for the future like MWNY (that is if Apple show up)?:(

spinner

Feb 25, 2003, 07:41 PM

Originally posted by MrMacman
Acually I read up on this and the 3.06 GHZ chip has hyperthreading ENABLED. The 2.6 ( I belive) chips and above have it but 3.06 and up can use it.
Intel was being sued by some company that had a trademark on it or something... they settled hence.
Intel 3.06 w/Hyperthreading.

Good call, I didn't realize that. If you have a link I wouldn't mind reading about the law suit.

mac15

Feb 25, 2003, 08:50 PM

the power5 won't be in the apple lineup as of yet but the power4 is supposedly going to be heading into macs, there was an article on neowin.net about.

The hyperthreaded p4s kicks ass, it focused all of its CPU on 2 apps at once, its kind of a cool feature. Hopefull it comes to the mac CPUs

ozubahn

Feb 25, 2003, 08:58 PM

The Power4/5 and derivatives are nice, but I'm going to take the really long view. I'm eagerly awaiting the day when we can laugh at Intel users with their 15GHz Pentiums, not because they are running at 15GHz, but because they still use system clocks. That's right, I want a nice new asynchronous Mac. A FleetZero (http://gmi.systemnews.com/system-news/jobdir/submitted/2001.10/4494/4494.html) based PowerBook, for instance, would be an excellent start. :)

(No, I am not waiting until we get asynchronous Macs before I upgrade, but I do think that's where we will be eventually.)

strider42

Feb 25, 2003, 09:31 PM

Originally posted by mac15
the power5 won't be in the apple lineup as of yet but the power4 is supposedly going to be heading into macs, there was an article on neowin.net about.

The hyperthreaded p4s kicks ass, it focused all of its CPU on 2 apps at once, its kind of a cool feature. Hopefull it comes to the mac CPUs

Once again, everyone say it with me now, the power4 and power5 will never be in a desktop machine. The 970 is a power4 derivitive that is intended for the desktop, but it is NOT the power4. for the same reasons as the power4, the power5 will never be in a desktop. Its just not suited for it.

Timothy

Feb 25, 2003, 09:44 PM

So...we're already looking beyond the 970?

I'd be happy with the 970, but we don't even have that.

york2600

Feb 25, 2003, 09:59 PM

This isn't entirely correct. The P4 Xeon processors where the first Intel chips to have the hyperthreading technology. I had 4 very sweet Dell PowerEdge servers that really confused me. The task manager said they had 4 processors when they were dual processor machines. Any program that is designed for multiple processors should be able to take full advantage of it. It's true that XP is the first OS to take advantage of hyperthreading. Windows 2003 Server has support as well. You can turn it off if you don't want to use it though (Windows NT/2k Server users possibly).

-Tim

Originally posted by spinner
Only the 3.06GHz P4 and later have Hyperthreading technology. Code must be specifically written to take advantage of it, and so far the only software I know that takes advantage of it is Windows XP. There could be others but I am not aware of any.

kenkooler

Feb 25, 2003, 10:00 PM

Originally posted by Timothy
So...we're already looking beyond the 970?

I'd be happy with the 970, but we don't even have that.

Hehe... reminds me of that Macosrumors.com article of Motorola chips up to G7

york2600

Feb 25, 2003, 10:06 PM

Here's a page by Intel that explains why you would want hyperthreading. Doesn't provide any real technical details, but might help some people here out.

http://www.intel.com/home/desktop/pentium4/hyperthreading.htm?iid=Homepage+htland_ihcp4ht&

twelve

Feb 25, 2003, 10:19 PM

just come out with it already.

Catfish_Man

Feb 25, 2003, 10:21 PM

In reply to a few of the posts here:
The 970 is single core without hyperthreading (or symmetric multithreading to be more accurate, hyperthreading is Intel's name for SMT). When the 970 goes to a .09 micron manufacturing process, dual core may become practical (.13 ->.09 cuts the transistor size in half) A POWER5 derivative seems fairly likely, and would have hyperthreading. The 4x performance boost from ht is widely regarded as ************ marketing claims, but it should give a fairly good boost (especially if the POWER4 isn't using its execution resources effectively. The Alpha EV8 was going to get a huge boost because it had way more execution units than it could normally use, and ht allowed it to use them more effectively). Neither the POWER4 nor the POWER5 will be used in Macs (the POWER4 costs several thousand dollars per chip, I've heard $7000-$8000). The 970 seems almost certain to be used in Macs (targetted at the desktop, has Altivec, etc...).

iwantanewmac

Feb 25, 2003, 10:39 PM

I bet this all isn't going to take place this year.....
First we get another lame G4 speedbump with some other minor updates that almost no1 uses.

ffakr

Feb 25, 2003, 10:55 PM

Originally posted by Catfish_Man
When the 970 goes to a .09 micron manufacturing process, dual core may become practical true... except I belive IBM said they have no plans for a multi-core 970. A POWER5 derivative seems fairly likely, and would have hyperthreading. The 4x performance boost from ht is widely regarded as ************ marketing claims, but it should give a fairly good boostIBM isn't claiming 4x performance increase from HT... they claim that their implementation is MUCH better than Intels and that a single core HT Power5 will really act like 2 processors. They claim 80-100% increase with their HT... proof remains to be seen. IBM has also said the core has been reworked so there are also performance improvements totally unrelated to HT.
Intel's HT, OTOH, seems to produce anything from a 20% increase to a 10% decrease in performance. Neither the POWER4 nor the POWER5 will be used in Macs It's way too early to make this claim. IBM is saying that the Power5 will go into big iron and smaller machines, though the implication is smaller servers. It will make sense, however, to bring the line together eventually instead of engineering two processors for each design generation. I personally wouldn't be surprised if a .13 micron or .09micron Power5 with a single core becomes the Mac chip in late 2004 or early 2005... but who knows.(the POWER4 costs several thousand dollars per chip, I've heard $7000-$8000). This is also pretty much impossible to say since the Power4 isn't put in anything but IBM servers. There is no $/1000 unit price, no raw or even retail price. Any figure generated for a Power4 module is the price for an IBM upgrade part for a high end server. I'd wager that if you wanted an IBM 'certified' Xeon, it'd cost a fortune too. I remember pricing additional Pentium 90 cards for old IBM 720 servers and they were around $1000... back when a P90 was a $30 part. Unfortunately, we needed to buy the card with with the CPU soldered onto it. The 970 seems almost certain to be used in Macs (targetted at the desktop, has Altivec, etc...). I think the real test of whether the Power5 makes it to the desktop is whether or not it includes Altivec. Apple would demand such support. IBM didn't think it was too important back in the day, but it has proved to be powerful and it would be useful in server situations.. so we'll see. :-)

Catfish_Man

Feb 25, 2003, 10:57 PM

Originally posted by iwantanewmac
I bet this all isn't going to take place this year.....
First we get another lame G4 speedbump with some other minor updates that almost no1 uses.

Seems fairly likely. A bump in early Q3 using 1.6GHz 7457s on the not officially recognized 200MHz bus (the way the 7455's Apple used had 167 before Motorola officially admitted it could), DDR400, maybe USB2, and maybe a new graphics card and/or AGP8x. Maybe a dual 1.33GHz 17" Powerbook :) (note: I rather doubt that, but it might be possible with the '57). Then in January they announce 1.4/1.6/1.8GHz PPC 970 based PowerMacs shipping in February.

<disclaimer> Everything above is, at best, an educated guess. </disclaimer>

ffakr

Feb 25, 2003, 11:06 PM

Originally posted by Catfish_Man
Seems fairly likely. A bump in early Q3 using 1.6GHz 7457s on the not officially recognized 200MHz bus (the way the 7455's Apple used had 167 before Motorola officially admitted it could), DDR400, maybe USB2, and maybe a new graphics card and/or AGP8x. Maybe a dual 1.33GHz 17" Powerbook :) (note: I rather doubt that, but it might be possible with the '57). Then in January they announce 1.4/1.6/1.8GHz PPC 970 based PowerMacs shipping in February.
I think Apple is acutely aware of the G4 problems and they'll get a 970 based machine out asap. I've no doubt that the machine is being developed with whatever pre-production processors that IBM can spare.
Maybe I'm just being an optimist.. but I expect a brand new 970 based Powermac sometime this year.
They can't afford to release a next gen machine one day later than necessary.

strider42

Feb 25, 2003, 11:54 PM

Originally posted by ffakr
I personally wouldn't be surprised if a .13 micron or .09micron Power5 with a single core becomes the Mac chip in late 2004 or early 2005... but who knows. This is also pretty much impossible to say since the Power4 isn't put in anything but IBM servers. There is no $/1000 unit price, no raw or even retail price. Any figure generated for a Power4 module is the price for an IBM upgrade part for a high end server. I'd wager that if you wanted an IBM 'certified' Xeon, it'd cost a fortune too. I remember pricing additional Pentium 90 cards for old IBM 720 servers and they were around $1000... back when a P90 was a $30 part. Unfortunately, we needed to buy the card with with the CPU soldered onto it. I think the real test of whether the Power5 makes it to the desktop is whether or not it includes Altivec. Apple would demand such support. IBM didn't think it was too important back in the day, but it has proved to be powerful and it would be useful in server situations.. so we'll see. :-)

It is absolutely impossible that the power4 or power5 will be in a desktop machine. absolutely, utterly impossible. Its not aimed at the desktop market. Its bulit for absolute reliability, and is thusly very expensive and gives up performance because of it. The power4 and power5 are absolutely NOT desktop chips, and no one in their right mind would use them as such. the 970 IS a desktop chip, designed to be so. if a power5 derivitive is made, that will be a desktop chip, but these are NOT the power4 and power5.

ddtlm

Feb 26, 2003, 12:14 AM

strider42:

It is absolutely impossible that the power4 or power5 will be in a desktop machine.
I know what you're trying to say, but technically it is not impossible... just exceedingly unlikely. They could make a $10k Power4 desktop which is evenly divided between heatsink, powersupply, and "other stuff". :)

gives up performance because of it
Yes, the whole design does sacrifice some performance, but there is no evidence that it will be any different for the PPC-970. As far as I can tell the only reasons why a PPC-970 will sometimes outperform a Power4 are: the 970 will be clocked higher, and it will have AltiVec.

ozubahn

Feb 26, 2003, 12:51 AM

Originally posted by ddtlm

Yes, the whole design does sacrifice some performance, but there is no evidence that it will be any different for the PPC-970. As far as I can tell the only reasons why a PPC-970 will sometimes outperform a Power4 are: the 970 will be clocked higher, and it will have AltiVec.

There is evidence, and you just pointed it out. The higher clock rate implies either a longer pipeline or thinner gate oxide (or both), the latter made possible by the reduced reliability requirements. These changes, along with a single-core die and vastly cheaper chip packaging, are what make the 970 and the POWER4 entirely different beasts. We can't guarantee that some hobbyist won't pick up an old POWER4 MCM at a swap meet years from now and stick it in a desktop box, but other than that, it isn't going to happen. The POWER5 may be a better hope, since IBM has suggested that it will move downmarket, but it still isn't likely.

ddtlm

Feb 26, 2003, 01:01 AM

ozubahn:

There is evidence, and you just pointed it out.
The higher clockrate is more likely possible for the same reasons for Xeons and Athlon MP's always are sold slower than their stand-issue brethren: lower standards, less testing. The effect of the smaller, single-core die could also be significant because of much better odds of the whole thing coming through with reduced speed-limiting defects. Power4+'s currently clock at up to 1.45ghz, not too far off the PPC-970's 1.8ghz, which obviously isn't even here yet.

but it still isn't likely
I never claimed otherwise.

hvfsl

Feb 26, 2003, 04:02 AM

I think we should dump moto and forget about IBM and go to Intel. The P4 is basically a risc chip that has a unit that converts x86 instructions to RISC and back again. What we need is a modified P4 that is PPC compatible, since Intel is the biggest chip maker in the world, this should not be too hard for them.

We would then always be able to keep up with the Windows world. The problems people have with Intel should also be left behind because Intel doesn't like M$, it is trying to find OS's that can replace Windows. It looked at getting BeOS at one point.

firestarter

Feb 26, 2003, 05:09 AM

Originally posted by ffakr
true... except I belive IBM said they have no plans for a multi-core 970.IBM isn't claiming 4x performance increase from HT... they claim that their implementation is MUCH better than Intels and that a single core HT Power5 will really act like 2 processors. They claim 80-100% increase with their HT... proof remains to be seen. IBM has also said the core has been reworked so there are also performance improvements totally unrelated to HT.
Intel's HT, OTOH, seems to produce anything from a 20% increase to a 10% decrease in performance.

The trouble with all these Intel comparisons is that Intel is a (quicly) moving target. The 970 may be competetive against the current range of Pentium 4s, but Intel will be another step ahead by the time the 970 is released.

From Anandtech: http://www.anandtech.com/showdoc.html?i=1790

"Intel's Prescott core will be their first CPU built on their new 90nm process, and is due out before the end of this year.

The updated Intel NetBurst micro-architecture comes in the form of an 800MHz FSB and a larger L1 data cache of 16KB, up from the 8KB of the Willamette and Northwood cores.

The improved Hyper-Threading technology in Prescott comes in the form of two new Hyper-Threading specific instructions, that are a part of the 13 total new instructions that made it into Prescott.

We've been mentioning for a while that Prescott will feature a large 1MB L2 cache, and Intel has publicly confirmed this at IDF. The 1MB L2 cache will bring Prescott up to around 100 million transistors, rivaling some of the most complex GPUs in transistor count.

The 90nm process combined with additional enhancements to Intel's manufacturing processes will allow the Prescott core to scale to the 4 - 5GHz range before it will be replaced by Tejas, which we mentioned earlier today. "

There is NO WAY that a 1.5 to 2GHz 970 is going to be faster than a 4 or 5 GHz Prescott (which also incidentally adds further Altivec style instructions, including specific support for video encoding).

DharvaBinky

Feb 26, 2003, 07:56 AM

Originally posted by spinner
Only the 3.06GHz P4 and later have Hyperthreading technology. Code must be specifically written to take advantage of it, and so far the only software I know that takes advantage of it is Windows XP. There could be others but I am not aware of any.

This is, in fact, incorrect. Software does not have to be rewritten to take advantage of SMT (Simultaneous MultiThreading the "real" name of HyperThreading). All software which runs on more than a single thread automatically takes advantage of HyperThreading. An example (and an anti-microsoft jab *grin*):

My team has written a large web app for universities to manage student flow that runs on Microsoft technologies such as SQL Server 2000. We're running our systems on Dell PowerEdge 2650 servers which feature Dual P4Xeons (with HyperThreading). Although the machine has *2* physical processors, Microsoft requires that we buy *4* processor licenses for SQLServer since the system appears as a quad processor machine to the Operating System. <OUCH> that put a big hurting on the 'ol budget there... SQLServer ain't cheap.

Apple and others need to watch out for this if/when IBM introduces the PPC980 (power 5 decendant), since many server software packages are licensed per processor (unlimited users). Windows 2003 purportedly solves this problem by recognizing HT processors, however... So, hopefully, Apple will learn from this MSNAFU and do it right in OS X the first time.

:)

Dharvabinky

Frobozz

Feb 26, 2003, 08:45 AM

Originally posted by hvfsl
I think we should dump moto and forget about IBM and go to Intel. The P4 is basically a risc chip that has a unit that converts x86 instructions to RISC and back again... We would then always be able to keep up with the Windows world...

UGH. lol.

ryan

Feb 26, 2003, 09:25 AM

Originally posted by wdlove
I was enthusiastic after reading the article. Now I'm depressed, is there any hope for the future like MWNY (that is if Apple show up)?:(
Apple will release a 970 based PowerMac when a 970 based PowerMac is ready. In case you've missed it Apple is now releasing products when they're ready and not waiting for some arbitrary date on the calendar, i.e. the Macworlds.

ffakr

Feb 26, 2003, 09:27 AM

Originally posted by firestarter
The trouble with all these Intel comparisons is that Intel is a (quicly) moving target. The 970 may be competetive against the current range of Pentium 4s, but Intel will be another step ahead by the time the 970 is released.

first off... I compared IBMs HT implementation to Intels HT... I didn't comprare the 970 to the P4. You are taking my comment out of context.

"Intel's Prescott core will be their first CPU built on their new 90nm process, and is due out before the end of this year.

The updated Intel NetBurst micro-architecture comes in the form of an 800MHz FSB and a larger L1 data cache of 16KB, up from the 8KB of the Willamette and Northwood cores. wow, another P4 built on the same core with upgraded stats. 8K of additional L1 cache (btw, I'd expect this to be instruction not data cache.. but what do I know).

The improved Hyper-Threading technology in Prescott comes in the form of two new Hyper-Threading specific instructions, that are a part of the 13 total new instructions that made it into Prescott.

We've been mentioning for a while that Prescott will feature a large 1MB L2 cache, and Intel has publicly confirmed this at IDF. The 1MB L2 cache will bring Prescott up to around 100 million transistors, rivaling some of the most complex GPUs in transistor count. So intel continues to build ever larger processors in the pursuit of ever diminishing returns. The Intel x86 project is quicly becoming the stereotypical 'American Musclecar'. Big, powerful, and not especially efficient. Even at .09 micron, I'm sure this will be a big chip... certainly big by the standards set by other .09 micron chips. I guess we'll have to wait to see if Intel runs into problems cooling such this sucker considering the number of gates in such a dense array.
The 90nm process combined with additional enhancements to Intel's manufacturing processes will allow the Prescott core to scale to the 4 - 5GHz range before it will be replaced by Tejas, which we mentioned earlier today. "

There is NO WAY that a 1.5 to 2GHz 970 is going to be faster than a 4 or 5 GHz Prescott (which also incidentally adds further Altivec style instructions, including specific support for video encoding). [/b]
Here is where your argument falls apart. The Prescott core will scale to 4-5 GHz. That is the speed predicted over the life of the core. The 970 will likely DEBUT at 1.5-2GHz, and the Prescott will DEBUT lower than 4-5GHz, but it may eventually scale that high. This is Extremely important. We don't know but a 1.8 or 2GHz introduction of 970 on .13 micron will very likely scale north of 3GHz on .09 micron. Will a 4GHz Prescott be faster than a 3GHz 970? We have no idea. The current SPEC seems to indicate that the 970 would give it a damn fine run for its money. :-)
Another thing to consider... do you expect a 5GHz P4 core to be 25% faster than a 4GHz P4 core? You don't expect these ultra high clock speeds to show substantially diminishing returns as the CPU runs away from the speed of the components?
IMHO... the key to this decade isn't 10GHz processors, it's more intelligent design. IBM is on the right track with what appears to be a much better SMT implementation and a smaller, more efficient cpu core. Even Sun seems to get it. They expect to have massive SMT and multi-cores per die... Sun hopes to have 8, 16, maybe 32 threads per processor die by 2005.

strider42

Feb 26, 2003, 09:37 AM

Originally posted by ddtlm
strider42:

I know what you're trying to say, but technically it is not impossible... just exceedingly unlikely. They could make a $10k Power4 desktop which is evenly divided between heatsink, powersupply, and "other stuff". :)

Yes, the whole design does sacrifice some performance, but there is no evidence that it will be any different for the PPC-970. As far as I can tell the only reasons why a PPC-970 will sometimes outperform a Power4 are: the 970 will be clocked higher, and it will have AltiVec.

Is it evidence enough that IBM THEMSELVES have talked about the differences between the 970 and the power4 and talk about how the 970 is actually faster in some areas because it isn't making compromises necessary for a server chip. Unless apple gets into the high end server business, it is utterly impossible this chip will ever be used by apple. OK, you are right its not technnically impossible, but the likelihood is just about 0. You can think what you want, but the 970 is too large, too expensive and makes too many compromises to be useful to apple. The 970 would be a better chip for apple in all possible areas except very high end servers. the 970 would be better as a workstation chip, a desktop chip and a mobile chip. There is nothing about the power4 that would even be remotely interesting to apple aside from the dual core aspect, which helps make it very expensive (among other things)

The 970 will be faster not because of altivec and higher clocks (althought hose certainly help), but because its not making compromises for reliability. IBM themselves have talked about this. If apple was going to use the power 4, they could have used it for nearly two years now. Its just not going to happen. its going to be the 970 and possibly a derivitive of the power5 if such a beast appears.

ffakr

Feb 26, 2003, 09:45 AM

Originally posted by strider42
It is absolutely impossible that the power4 or power5 will be in a desktop machine. absolutely, utterly impossible. Its not aimed at the desktop market. Its bulit for absolute reliability, and is thusly very expensive and gives up performance because of it. The power4 and power5 are absolutely NOT desktop chips, and no one in their right mind would use them as such. the 970 IS a desktop chip, designed to be so. if a power5 derivitive is made, that will be a desktop chip, but these are NOT the power4 and power5.
First off... I never said the Power4 would be in a Mac. Drop that part, it's a non-issue.

Your argument doesn't make any sense though. Just because it is reliable doesn't mean it won't work in a desktop. Just because it is currently prohibitivly expensive doesn't mean it won't work in a desktop (though market forces would make it impractical).

There is nothing in the architecture of a processor that makes it inherently expensive to create. Cost is related to R&D, Demand, Supply, Production costs (size, yield,...). It isn't related to the way in which the gates are arranged in a litho mask.
Server processors do tend to have thicker gates and interconnects to increase reliabilty, but even this is a minor extra cost. They are also sorted to a higher standard than desktop parts, increasing testing cost and decreasing yeild.
Once the 'maze' of the architecture is laid down, the trivial part would be shrinking the 'walls'. It would be a LOT easier than maintaining an architecture and a derivative of that architecture.

Now, look at my argument again. What makes more sense, making a Power5 for the desktop/small server or making a Power5 and yet another architecture based off of the Power5? The cost associated with making a desktop Power5 is MUCH lower than making a derivative architecture... and the dev time would be much shorter too.

As I said... I don't know if a Power5 will end up in a Mac and you certainly don't either. IBM is hinting (over a year out) that this processor will run in smaller hardware than the Power4 was designed to run in. The Power4+ (smaller die) is being put into smaller servers already. Add to this the fact that NO ONE knows what a Power4 really costs because the only info you have is the cost of an IBM aftermarket upgrade part (which is an IBM branded module with a big L3 cache)... not a raw chip price. IBM doesn't sell them to anyone else, so we have no idea. We have no idea how increased production and increased supply for a much larger market would affect the production cost of a chip like the Power4+ and we certainly don't know how it would affect a processor like the Power5... which just got powered on 2 weeks ago.

I think the key to whether we may see a real Power5 in a Mac would be whether or not IBM includes Altivec in the Power5, and what the transistor count turns out to be.

One more thing... if IBM does design the Power5 to be an option for the Mac, the increased production will drive down per unit cost. This means larger margins and more competitive prices for their Enterprise hardware.... their largest business unit.

ffakr

Feb 26, 2003, 09:54 AM

Originally posted by strider42
The 970 will be faster not because of altivec and higher clocks (althought hose certainly help), but because its not making compromises for reliability. IBM themselves have talked about this. If apple was going to use the power 4, they could have used it for nearly two years now. Its just not going to happen. its going to be the 970 and possibly a derivitive of the power5 if such a beast appears.

I believe that Power4+ IS as fast or faster than the 970 when you don't consider the MHz increase.

from SPEC.org
IBM pSeries 650 Model 6M2 (1450 MHz, 1 CPU) 1 909 935
IBM eServer 655 Model 651 (1300 MHz, 1 CPU) 1 822 848

estimated SPEC for the 970 at 1.8 GHz are about the same for Int and slightly higher for FP. IBM says the 970 numbers will likely go up as they near production, but I think a 1.45GHz Power 4 would hold its own against a similarly clocked 970.... don't you?

scem0

Feb 26, 2003, 10:06 AM

Originally posted by howard
all we can do is wait... lets just hope we don't have to for very long!!

yeah, we won't be seeing this chip in a mac for a looooooong
time, if ever... so I think it would be best if we all just tried not
to relive the whole 'g5 is coming!' thing again.

'The power5 is coming!' :rolleyes:

MacRETARD

Feb 26, 2003, 10:54 AM

applejilted

Feb 26, 2003, 11:04 AM

The danger with IBM is, IMHO, that IBM is also a a major server manufacturer and as such wants to incorporate its chips in its boxes. Apple has a modestly successful server product (Xserve with OS X server software) will IBM want to supply Apple with their Power5 chip (albeit not the multicore variety) so Apple could compete with IBM in what IBM considers a crucial market ? This may seem trivial now as Apple is a mere minnow in the server market comapred to Big Blue or SUN but don't think for one moment that IBM hasn't thought about this .... they'll want to cripple the Power5 so much that it will pose no threat to their server sales. In a way that's the beauty of buying from Intel they won't compete with you.

strider42

Feb 26, 2003, 11:10 AM

Originally posted by ffakr
First off... I never said the Power4 would be in a Mac. Drop that part, it's a non-issue.

Your argument doesn't make any sense though. Just because it is reliable doesn't mean it won't work in a desktop. Just because it is currently prohibitivly expensive doesn't mean it won't work in a desktop (though market forces would make it impractical).

There is nothing in the architecture of a processor that makes it inherently expensive to create. Cost is related to R&D, Demand, Supply, Production costs (size, yield,...). It isn't related to the way in which the gates are arranged in a litho mask.
Server processors do tend to have thicker gates and interconnects to increase reliabilty, but even this is a minor extra cost. They are also sorted to a higher standard than desktop parts, increasing testing cost and decreasing yeild.
Once the 'maze' of the architecture is laid down, the trivial part would be shrinking the 'walls'. It would be a LOT easier than maintaining an architecture and a derivative of that architecture.

Now, look at my argument again. What makes more sense, making a Power5 for the desktop/small server or making a Power5 and yet another architecture based off of the Power5? The cost associated with making a desktop Power5 is MUCH lower than making a derivative architecture... and the dev time would be much shorter too.

As I said... I don't know if a Power5 will end up in a Mac and you certainly don't either. IBM is hinting (over a year out) that this processor will run in smaller hardware than the Power4 was designed to run in. The Power4+ (smaller die) is being put into smaller servers already. Add to this the fact that NO ONE knows what a Power4 really costs because the only info you have is the cost of an IBM aftermarket upgrade part (which is an IBM branded module with a big L3 cache)... not a raw chip price. IBM doesn't sell them to anyone else, so we have no idea. We have no idea how increased production and increased supply for a much larger market would affect the production cost of a chip like the Power4+ and we certainly don't know how it would affect a processor like the Power5... which just got powered on 2 weeks ago.

I think the key to whether we may see a real Power5 in a Mac would be whether or not IBM includes Altivec in the Power5, and what the transistor count turns out to be.

One more thing... if IBM does design the Power5 to be an option for the Mac, the increased production will drive down per unit cost. This means larger margins and more competitive prices for their Enterprise hardware.... their largest business unit.

reliability has a direct effect on speed. The pwoer4's are made to be absolutely bullet proof. I froget allt he technical details, but its absolutely affects how fast a processor is. IBM wasn't going for the fastest chip whenh they made the power4. They were going for the best server chip, which includes being about the most reliable chip on the market. This makes it more expensive and sacrifices speed. This is absolute fact. My argument is sound.

With that in mind, thats why apple would never use it in a desktop, nor would anyone else. It makes it expensive, it makes it big, it makes compromises that don't need to be made for desktop machines. You don't use a mac truck to get around town.

It makes perfect sense for IBM to make a server chip, and then make a derivitive of it. You can't use one size fits all chips when you are making servers that costs in the hundreds of thousands of dollars range. The power4 and power5 will never be in a desktop. Is it possible the power5 will be more flexible, sure it is. But there is absolutely no evidence that it will be a desktop chip, whereas it is absoltuely positive it will be s erver chip. Given that, and the pecedent with the power4 and 970, it makes much more sense that there may be a power5 derivitive chip, but it won't be the power5.

I'm not trying to just be argumentative, but just trying to point out there is absolutely nothing anywhere that points to the power5 being anything more than a server chip, where as there is evidence and precedent for a derivitive chip to be made, adn that server and desktop chips have different priorities.

strider42

Feb 26, 2003, 11:11 AM

Originally posted by ffakr
I believe that Power4+ IS as fast or faster than the 970 when you don't consider the MHz increase.

from SPEC.org
IBM pSeries 650 Model 6M2 (1450 MHz, 1 CPU) 1 909 935
IBM eServer 655 Model 651 (1300 MHz, 1 CPU) 1 822 848

estimated SPEC for the 970 at 1.8 GHz are about the same for Int and slightly higher for FP. IBM says the 970 numbers will likely go up as they near production, but I think a 1.45GHz Power 4 would hold its own against a similarly clocked 970.... don't you?

Yes, but IBM has stated that the 970 would be faster than the power4 in some instances, I believe because of the priorities of design in the chip. The power4 is probably faster overall in a lot of areas, but the 970 will hold its own against it. Which is relaly the point. The 970 will be smaller, cheaper and mroe available, and over similar performance to a top tier server chip.

ffakr

Feb 26, 2003, 11:14 AM

Originally posted by applejilted
The danger with IBM is, IMHO, that IBM is also a a major server manufacturer and as such wants to incorporate its chips in its boxes. Apple has a modestly successful server product (Xserve with OS X server software) will IBM want to supply Apple with their Power5 chip (albeit not the multicore variety) so Apple could compete with IBM in what IBM considers a crucial market ?
Insightful point... but IBM's idea of a server and Apple's idea of a server are radically different. IBM make Billions (with a big FAT B) by selling Big Iron. That is mainframes and boxes with many CPUs that cost over $100,000 each (on the low end). Apple will never be a competetor here.
IBM has only recently started putting Power4+ chips (within the last few days) into their 'low end' unix boxes... the ones that start at $15,000 stripped... and usually ship with a much bigger price tag than that.

this could all change if Apple goes after Grid computing in a big way with PPC based clusters and small commodity linux servers, but this isn't a big component of their sales at this point.
... It's not like apple is going to release 16 or 32way PPC 970 boxes this fall. :-)

ffakr

Feb 26, 2003, 11:17 AM

Originally posted by strider42
Yes, but IBM has stated that the 970 would be faster than the power4 in some instances, I believe because of the priorities of design in the chip. The power4 is probably faster overall in a lot of areas, but the 970 will hold its own against it. Which is relaly the point. The 970 will be smaller, cheaper and mroe available, and over similar performance to a top tier server chip.
The power 4 is also designed to be a dual core processor and it keeps up with the 970 with only one of if its cores. It is important to note that any Power4 (unless intentionally crippled by IBM) would post nearly twice the scores of the 970 due to the dual cores.
Of course the 970 will be smaller, it's less than half the chip, with Altivec tacked on. The 970 doesn't need to be designed with the extra dual core logic that makes the Power4 such a great processor.

sergeantmudd

Feb 26, 2003, 01:24 PM

Originally posted by applejilted
The danger with IBM is, IMHO, that IBM is also a a major server manufacturer and as such wants to incorporate its chips in its boxes. Apple has a modestly successful server product (Xserve with OS X server software) will IBM want to supply Apple with their Power5 chip (albeit not the multicore variety) so Apple could compete with IBM in what IBM considers a crucial market ?

I remember reading about IBM couldn't meet the demand for p690 when it came out because there was a shortage of Power4 chips. The shortage of Power4 chips was a result of their chip foundry being too busy stamping out PA-RISC and Alpha chips for HP and Compaq. IBM realizes that companies like Apple, HP, and Compaq are going to be competitive with or without IBM's help, so IBM might as well make some money helping them out.

firestarter

Feb 26, 2003, 01:31 PM

Originally posted by ffakr
first off... I compared IBMs HT implementation to Intels HT... I didn't comprare the 970 to the P4. You are taking my comment out of context.

The only point I wanted to make here was to point out that Intels HT is being addressed and improved.

wow, another P4 built on the same core with upgraded stats. 8K of additional L1 cache (btw, I'd expect this to be instruction not data cache.. but what do I know).
So intel continues to build ever larger processors in the pursuit of ever diminishing returns. The Intel x86 project is quicly becoming the stereotypical 'American Musclecar'. Big, powerful, and not especially efficient. Even at .09 micron, I'm sure this will be a big chip... certainly big by the standards set by other .09 micron chips.

Well spotted about the 'data cache' - you're probably right (original quote is from Anandtech - they should be more careful).

I have an engineering background and like elegant designs as much as the next person... but unfortunately this game isn't a design beauty parade, it's about IBM/Moto/Apple keeping up with Intel in speed.

I guess we'll have to wait to see if Intel runs into problems cooling such this sucker considering the number of gates in such a dense array.

Agreed. Intel seems to be wise to this - whitness the birth of Bandinas/Centrino on the laptop - where Intel's gone back to shorter pipelines and more design efficiency to build a chip that's much more power/clock efficient than the P4.

Here is where your argument falls apart. The Prescott core will scale to 4-5 GHz. That is the speed predicted over the life of the core. The 970 will likely DEBUT at 1.5-2GHz, and the Prescott will DEBUT lower than 4-5GHz, but it may eventually scale that high. This is Extremely important. We don't know but a 1.8 or 2GHz introduction of 970 on .13 micron will very likely scale north of 3GHz on .09 micron. Will a 4GHz Prescott be faster than a 3GHz 970? We have no idea. The current SPEC seems to indicate that the 970 would give it a damn fine run for its money. :-)

Actually I disagree. SPECmark ratings have been widely published - one report was on:
http://www.aceshardware.com/read_news.jsp?id=60000475

This shows the 1.8G 970 testing slower than the 3.06G P4. I would expect an improved P4 core with cache/architectural improvements, running at 4GHz to be faster!

Another thing to consider... do you expect a 5GHz P4 core to be 25% faster than a 4GHz P4 core? You don't expect these ultra high clock speeds to show substantially diminishing returns as the CPU runs away from the speed of the components?

Front side bus speed is also massively increased, and the L2 cache size is doubled. Returns will deminish, but I would expect most of this increase in speed to be realised. On the desktop, media handling (compression/decompression etc.) is the application most folks will want a speedup in, and this is tight code which will fit in the cache.

IMHO... the key to this decade isn't 10GHz processors, it's more intelligent design. IBM is on the right track with what appears to be a much better SMT implementation and a smaller, more efficient cpu core. Even Sun seems to get it. They expect to have massive SMT and multi-cores per die... Sun hopes to have 8, 16, maybe 32 threads per processor die by 2005.
I agree, except that I'd add that the important thing will be software design. Most folks want to see a speed increase in the straight line performance of the single app they're running, and this is an important difference in requirements to the Sun server chips you cite. Apple need to get their developers making better use of threads and Altivec, so that users do experience these speed increases on parallel processors.

type_r503

Feb 26, 2003, 01:50 PM

quote from page 2

"Robert Scoble writes in his weblog:

I've had some sneaks behind the scenes (not official ones, though). Apple has some cool stuff coming this year to be sure -- including some desktop machines that are outperforming current Intel stuff."

spinner

Feb 26, 2003, 03:05 PM

Taken from Intel's website:

Hyper-Threading Technology has arrived on the desktop. Look for systems with the new Intel® Pentium® 4 Processor with HT Technology logo which your system vendor has verified utilize Hyper-Threading Technology. Performance will vary depending on the specific hardware and software you use. To carry the Intel® Pentium® 4 Processor with HT Technology logo, systems must have:

The Intel Pentium 4 processor at 3.06 GHz or higher
An Intel® chipset that supports HT Technology
System BIOS supports HT Technology and has it enabled
An operating system (http://www.intel.com/support/platform/ht/os.htm) that includes optimizations for HT Technology
Click here (http://www.intel.com/homepage/land/hyperthreading.htm) for an overview of the Pentium 4 Processor with HT Technology.

I guess that I was under the impression that this technology runs into the same problem that some Mac apps do, they are not multithreaded or MP aware and do not see the extra speed advantages that they could. Now I am not an expert so if this is wrong please explain why so that we all can know.

DharvaBinky

Feb 26, 2003, 04:01 PM

Originally posted by spinner
I guess that I was under the impression that this technology runs into the same problem that some Mac apps do, they are not multithreaded or MP aware and do not see the extra speed advantages that they could. Now I am not an expert so if this is wrong please explain why so that we all can know.

You're pretty much right. But when they say "Operating system optimized to use HT" they're really talking about "Operating system that supports MultiProcessing". This rules out Windows 95, 98, 98se, and winMe. Windows NT4, 2000(all versions), and xp(all versions) support at least 2 processors.

http://www.pro-paganda.com/images/ht-madness.jpg

This is on one of my production servers. It's a Dell PowerEdge 2650 (http://www.dell.com/us/en/hied/products/model_pedge_1_pedge_2650.htm) which supports dual P4Xeons (the original P4s to have HT).

Notice in the above image, that the Dell ServerManager software correctly identifies that there are two P4 Xeons at 2.4GHz in the system. Nice, right? Now look at the graph below it. That's a small capture from the Microsoft Performance Monitor. Notice that it shows that there are 4 processors being charted. This is because windows *assumes* that every "thread" available is because there is another processor to run it. Win2k3 is supposed to solve this problem by correctly identifying HT processors.

So yes... earlier versions of windows have the same single thread limitation that mac os 9 and earlier has. OS X, though, would be able to support HT with no modification. However, as I mentioned before, Apple would do well to prepare OS X ahead of time for SMT Technologies (Simultaneous MultiThreading, the generic name for the technology, HT is Intel's trademarked Marchitechture name) to prevent the same headaches I am experiencing right now from Wintel's slapshod adoption.

The big hit, for us, has been in the pocket book. Since windows incorrectly identifies the dual HT Xeons as quad processors, it messes with our licensing. All of our server products and components are licensed for unlimited users. So the big difference is the number of *processors* that they are licensed to run on. The specific OUCH for us has been the licensing costs for SQL server which runs on a per processor license. MS has stated that HT "virtual processors" count as processors for the licensing of SQL server 2000. OUCH, that doubled our projected database costs...

On the upside, though... We're noticing *significant* performance gains from the HT. Database access and script parsing/execution lend themselves well to multi-threading, especially since we run 22 "virtual instances" of our web app on each of our WebFarm machines (accessing a centralized database). If you turn off HT (which is possible to do in the BIOS), we lose about 30 speed. No small potatoes.

Look to see PPCs with HT showing up in server apps first where they'll get the most benefit. End users will get *some*, but since most end-user apps (word processing, games) are single thread apps, don't look to get too much extra bang from these systems when they make it to the consumer line... (this goes for dell using P4s with HT, too)

:)

Dharvabinky

ddtlm

Feb 26, 2003, 04:07 PM

strider42:

The 970 will be faster not because of altivec and higher clocks (althought hose certainly help), but because its not making compromises for reliability. IBM themselves have talked about this.
You should share where IBM said this, because until you can do that I'll go on believing you're restating rumors. Myself and others have already told you that on 130nm tech, a Power4+ can run at 1.45ghz. Having the PPC-970 run at 1.8ghz sometime down the road most certainly does not imply that any of these uspecified changes where made to the core as you claim. For example, Intel's big-cache Xeon MP is available at only up to 2.0ghz despite the fact that it has the same core and same manufacturing tech as P4's clocking a full 50% higher. Is it really so hard for you to believe that adding large amounts of L2 and a second core, plus more conservative clock speed safety margins, could account for the small difference between 1.45ghz and 1.8ghz?

Now, I suppose you could claim that IBM did some "things" to make the PPC-970 faster in ways other than clockspeed, because of the nebulous idea that not as many unspecified "compromises for reliability" where made. One of these things would be the AltiVec unit. However IBM makes no mention of any other core changes or improvments in the sole official document I am aware of:

http://www-3.ibm.com/chips/techlib/techlib.nsf/techdocs/A1387A29AC1C2AE087256C5200611780

reliability has a direct effect on speed. The pwoer4's are made to be absolutely bullet proof. I froget allt he technical details, but its absolutely affects how fast a processor is. IBM wasn't going for the fastest chip whenh they made the power4. They were going for the best server chip, which includes being about the most reliable chip on the market. This makes it more expensive and sacrifices speed. This is absolute fact. My argument is sound.
Your arguments have no value without proof.

Yes, but IBM has stated that the 970 would be faster than the power4 in some instances, I believe because of the priorities of design in the chip.
Priorities that allowed the higher allowed clockspeed and the AltiVec units.

MacRETARD:

The Intel XEON chips also have HT.
It's Xeon, not XEON.

ffakr:

8K of additional L1 cache (btw, I'd expect this to be instruction not data cache.. but what do I know)
The P4 does not have an instruction cache as normal chips would, instead it has a "trace cache" where decoded instruction streams are kept. The size of this is not clearly defined.

The power 4 is also designed to be a dual core processor and it keeps up with the 970 with only one of if its cores. It is important to note that any Power4 (unless intentionally crippled by IBM) would post nearly twice the scores of the 970 due to the dual cores.
Only in the right task.

ktlx

Feb 26, 2003, 04:19 PM

Originally posted by DharvaBinky
You're pretty much right. But when they say "Operating system optimized to use HT" they're really talking about "Operating system that supports MultiProcessing". This rules out Windows 95, 98, 98se, and winMe. Windows NT4, 2000(all versions), and xp(all versions) support at least 2 processors.

Mostly true. Windows XP Home does not support multiple processors while Windows XP Professional does. It is one of the roughly three significant differences between the two OSes.

Dont Hurt Me

Feb 26, 2003, 04:26 PM

I see it now, apple announces the the new g5! a 7457 g4 this summer and all that talk of the 970 goes out the window. Now what?

Telomar

Feb 26, 2003, 04:26 PM

Originally posted by ddtlm
You should share where IBM said this, because until you can do that I'll go on believing you're restating rumors. Myself and others have already told you that on 130nm tech, a Power4+ can run at 1.45ghz. Having the PPC-970 run at 1.8ghz sometime down the road most certainly does not imply that any of these uspecified changes where made to the core as you claim. For example, Intel's big-cache Xeon MP is available at only up to 2.0ghz despite the fact that it has the same core and same manufacturing tech as P4's clocking a full 50% higher. Is it really so hard for you to believe that adding large amounts of L2 and a second core, plus more conservative clock speed safety margins, could account for the small difference between 1.45ghz and 1.8ghz?

In an article published in Microprocessor Reports in 1999, IBM described its use of thicker gate oxides in the POWER4 processor to obtain a failure rate that is two orders of magnitude better than comparable processors from most other manufacturers. The cost of the thicker oxides is the reduced drive current of the transistor and consequently slower switching speed of the transistors on the POWER4 processor. In the case of the PowerPC 970, the processor does not need to meet similar reliability requirements as the POWER4 processor, and as a consequence, circuit and process technology can be tweaked to obtain higher performance by trading away the near-absolute reliability required by the POWER4 processor.

Just because you don't know it or because it isn't made easily available doesn't mean it isn't true.

ddtlm

Feb 26, 2003, 04:30 PM

Telomar:

Just because you don't know it or because it isn't made easily available doesn't mean it isn't true.
Not a very useful approach for separating fact from rumors.

Anyway, your quote of that microprocessor report fails to address the issue. I have never claimed that the Power4 is not conservatively designed and manufactured, I have claimed that there is no evidence that the PPC-970 has not inherited the same conservative features. To be clear: your quote says "can". It appears to be speculation.

RIP

Feb 26, 2003, 04:30 PM

Originally posted by ozubahn
The Power4/5 and derivatives are nice, but I'm going to take the really long view. I'm eagerly awaiting the day when we can laugh at Intel users with their 15GHz Pentiums, not because they are running at 15GHz, but because they still use system clocks. That's right, I want a nice new asynchronous Mac. A FleetZero (http://gmi.systemnews.com/system-news/jobdir/submitted/2001.10/4494/4494.html) based PowerBook, for instance, would be an excellent start. :)

(No, I am not waiting until we get asynchronous Macs before I upgrade, but I do think that's where we will be eventually.)

WOW

ddtlm

Feb 26, 2003, 04:39 PM

Telomar:

To continue my previous post, which I think is very unclear, I think that even if it is true that the PPC-970 is designed and produced without the thick oxides and whatever, then my whole arguement is still standing. Each time that I speak about the occasional performance edge of a PPC-970 over a Power4, I list clock speed as an advantage, which is covered by your quote. (Sure hope that was more clear, I can't talk for some reason.)

Telomar

Feb 26, 2003, 04:46 PM

Originally posted by ddtlm
Anyway, your quote of that microprocessor report fails to address the issue. I have never claimed that the Power4 is not conservatively designed and manufactured, I have claimed that there is no evidence that the PPC-970 has not inherited the same conservative features. To be clear: your quote says "can". It appears to be speculation. It doesn't really bother me one bit whether you take it for speculation but that actually comes from comments made at the Microprocessor Forum. I can tell you it's quite true and what strider42 said is in fact quite correct that's just the only current public information (to my knowledge).

There are changes between the POWER4 and 970 that although not always major will allow for better clock speeds and scaling of the chip. You can either trust the fact that I have access to significantly more information that makes me certain on this or you can continue to choose to be arrogant and naive. But it'd be nice if you stopped misleading the boards with your ignorance on this matter. Sometimes you can get "proof" that is completely incorrect and sometimes you can't get public information on things that are true. That's just the way the world is.

ddtlm

Feb 26, 2003, 05:20 PM

Telomar:

You can either trust the fact that I have access to significantly more information that makes me certain on this or you can continue to choose to be arrogant and naive. But it'd be nice if you stopped misleading the boards with your ignorance on this matter.
Needless to say I am surprised to find myself accused of arrogance when I demand proof on forums that are every day flooded by wild speculation, heresay, and plain wrong notions.

There are changes between the POWER4 and 970 that although not always major will allow for better clock speeds and scaling of the chip.
Interestingly you will find that the original point of the argument between strider42 and myself was not about scaling at all, for example strider42 said:

The 970 will be faster not because of altivec and higher clocks (althought hose certainly help), but because its not making compromises for reliability. IBM themselves have talked about this.
Now, as you can see, noone has provided anything that IBM said about this, and all the advantages you speak of are clock speed related. So, where does that leave you and your accusations about me?

I can tell you it's quite true and what strider42 said is in fact quite correct that's just the only current public information (to my knowledge).
Are you sure that you know what strider42 is argueing? If you are, then perhaps you should address that, and not address clock speed scaling.

Additionally, there are other issues I have mentioned, such as the very narrow clock speed advantage that the rather small PPC-970 is projected to have over a Power4+ (which is shipping at 1.45ghz right now). I would be interested to know where all the clock speed scaling advantages are at, should you happen to know.

ewinemiller

Feb 26, 2003, 08:35 PM

Originally posted by ktlx
Mostly true. Windows XP Home does not support multiple processors while Windows XP Professional does. It is one of the roughly three significant differences between the two OSes.

I think I read somewhere that while XP Home won't support two physical processors, it does support the two logical processors the hyperthreading presents. So you can install XP home on your 3.06 and it will use the hyperthreading.

ktlx

Feb 26, 2003, 09:44 PM

Originally posted by ewinemiller
I think I read somewhere that while XP Home won't support two physical processors, it does support the two logical processors the hyperthreading presents. So you can install XP home on your 3.06 and it will use the hyperthreading.

Ooops, you are correct. Windows XP Home will support two logical processors. My mistake.

KingArthur

Feb 27, 2003, 12:27 AM

Originally posted by Catfish_Man
In reply to a few of the posts here:
The 970 is single core without hyperthreading (or symmetric multithreading to be more accurate, hyperthreading is Intel's name for SMT). When the 970 goes to a .09 micron manufacturing process, dual core may become practical (.13 ->.09 cuts the transistor size in half) A POWER5 derivative seems fairly likely, and would have hyperthreading. The 4x performance boost from ht is widely regarded as ************ marketing claims, but it should give a fairly good boost (especially if the POWER4 isn't using its execution resources effectively. The Alpha EV8 was going to get a huge boost because it had way more execution units than it could normally use, and ht allowed it to use them more effectively). Neither the POWER4 nor the POWER5 will be used in Macs (the POWER4 costs several thousand dollars per chip, I've heard $7000-$8000). The 970 seems almost certain to be used in Macs (targetted at the desktop, has Altivec, etc...).

Just FYI, Hyperthreading is Simultaneous Multithreading, not symetric multithreading. I believe you were mixing up the term with symetric multiprocessing (what the dual processors do)

Also, the Intel Xenon chip is actually a P4 processor with unique features not added to the regular P4. Hyperthreading was one of these, but now the P4 utilizes this, so there is one less reason to get a Xenon processor.

Simultaneous Multithreading (hyperthreading) is both a good thing and a bad thing. Tests done with the Xenon differ greatly in performance with SMT turnned on and off. The problem with SMT is that sometimes one of the two programs being processed consumes too much of the cache resources. Then, the other program is starved of resources. The Xenon/P4 chips only put limits on the processor's execution resources, not memory resources. Therefore, a process can only use up half of the processor's queue slots, but all of the memory registers. Thus, one process has nothing in the cache and can't fill the other execution slots (which is the advantage of SMT). B/c the operating system thinks of them as two processors, it doesn't budget the "time-slicing". "Time-slicing" gives a process so many cycles of the processor's undivided attention and memory resources and then removes all of it from the processor's memory registers and puts it into a higher level of memory, and then brings in the next process, which has undivided attention etc. With the SMT, though, the OS thinks that, since there are two processors, each processor must have its own resources. The processor isn't designed to budget the memory resources, and one process, although constantly looking through the memory registers for its next part to process, never recieves anything to process b/c the other is a hog.

Another thing, someone posted that programs would have to be rewritten to take advantage of SMT. Yes and No. The only reason a program would have to be written to take advantage of SMT is if it is wanting to process two of its own threads simultaneously. The WinXP OS is designed to Hyperthread two applications. Applications would have to be written if they want to Hyperthread themselves.

Long story short, unless a hyperthreaded Power4 derivative is designed to budget all resources, there will be the same short commings as the Xenon/P4.

Also, someone earlier posted that the 970 and Power5 have not been produced. That is a false statement. The 970 is already being prepared for distribution. The Power5 has been produced and already been used in a test machine. That isn't to say it is complete, but it has been produced and is being tested to work bugs out of it.

That is my 50cents worth (or whatever value you think what I had to say has). For more info on Hyperthreading, go to http://arstechnica.com/paedia/h/hyperthreading/hyperthreading-1.html , although I do not know if everyone will be able to comprehend what is said. Ars Technica is a valuable resource for people wanting to learn how processors work from simple explanations to complex ones.

ffakr

Feb 27, 2003, 10:15 AM

Originally posted by KingArthur
Just FYI, ...Also, the Intel Xenon chip is actually a P4 processor ....

FYI... It's a Xeon, not a Xenon. Xenon is a gas used in lighting. ;-)

Catfish_Man

Feb 27, 2003, 03:40 PM

Originally posted by KingArthur

That is my 50cents worth (or whatever value you think what I had to say has). For more info on Hyperthreading, go to http://arstechnica.com/paedia/h/hyperthreading/hyperthreading-1.html , although I do not know if everyone will be able to comprehend what is said. Ars Technica is a valuable resource for people wanting to learn how processors work from simple explanations to complex ones.

Agreed. I've read almost everything they've published, and it's all been useful (aside from a few old CPU specific things like overclocking 300MHz Celerons that I skipped).

GeneR

Feb 27, 2003, 06:40 PM

For me, I use FCP and After Effects most of the time. I do a lot of archiving of stock footage from DV and most of it has some tweaking aspect to it. You could say, I'm building a stock DV library for future shoots. But the rendering for all the different shots takes so darn long that I am often rather put off by the fact that my Mac is tied up for hours (but more often) days.

And that really sucks.

I am hoping that this will change if there are faster chips, but with all the talk about 970-this and 970-that I really do not know. How does it compare to, say, 1 GHz G4? Or even a 1.4 GHz Dual G4? I'm still waiting for the day when I can shoot footage, go back to the desktop, load the stuff in, archive it and move forward.

Any thoughts about speed performance in respect to rendering would be appreciated.

ffakr

Feb 28, 2003, 03:24 PM

Originally posted by GeneR
I am hoping that this will change if there are faster chips, but with all the talk about 970-this and 970-that I really do not know. How does it compare to, say, 1 GHz G4? Or even a 1.4 GHz Dual G4?

Hard to say... until we get one.
Based on SPEC (which the G4 runs poorly), the 1.8 GHz 970 should be about as fast as a new Dual G4... that would be if you were running code that took full advantage of both processors.

I'd guess and estimate that a single 970 would probably keep up with a new dual (faster in some things.. especially where the bus was concerned).
It could be quite a bit faster based on what IBM is alluding to, based on the architecture and the new, higher clock announcements.

Now, what Apple really needs to do is release at least one dual 970 box a the introduction. It may be too much to expect all duals since the chips will be scarce at first.
Dual processor x86 boxes fetch a premium. If Apple can get a dual 970 out, they'd probably beat wintel (amd-tel) on price/performance and quite possibly raw performance.... one can only hope.

ffakr.

mathiasr

May 24, 2003, 05:20 PM

The latest news related to the POWER5.

The chip is still expected around 1.5 GHz in the first half of next year:
http://www.eweek.com/article2/0,3959,1093901,00.asp

Early samples boot under LinuxPPC64:
http://marc.theaimsgroup.com/?l=linux-ppc&m=104791921406815&w=2

IBM has already produced at multithreaded chip the RS64 IV:
http://www.research.ibm.com/journal/rd/446/borkenhagen.html

A good chronology of the POWER, RS and PowerPC families:
http://www.rootvg.net/column_risc.htm

Cubeboy

May 25, 2003, 05:55 PM

Hyperthreading (Simultaneous Multi-Threading) follows the same general rules of dual processors (since it is essentially two processors except they share one set of integer-math, floating-math, SSE and code-decode units), the better threaded a application is, the greater the performance increase between a hyperthreaded processor and and it's non-hyperthreaded variant.

Cubeboy

May 25, 2003, 06:52 PM

The advantages of Prescott over Pentium 4 are as follows:
1) Higher clockspeeds (5+ GHzs compared to 3.2 GHzs)
2) Twice the L1 Data Cache (16 Kb compared to 8 Kb)
3) Larger L1 Trace Cache (16 Kb compared to 12 Kb)
4) Trace Cache Bandwidth (4 uOps/cycle vs 3uOps/cycle)
5) Twice the L2 Cache (1024 Kb compared to 512 Kb)
6) Better branch predictor (Better prefetch, higher IPC)
7) Lower Latency (Overall better performance)
8) Improved Hyperthreading (reduced collision of threads)
9) SSE3 (better performance in gaming, media, scientific apps)
10) Additional Write Combining Buffers

Their is also a good possibility of a faster system bus, the current P4's bus is already clocked 800 mhz fsb, Prescott's bus will probably be clocked at either 1066 mhz or 1200 mhz.

mathiasr

May 26, 2003, 02:35 AM

Originally posted by Cubeboy
The advantages of Prescott over Pentium 4 are as follows:
1) Higher clockspeeds (5+ GHzs compared to 3.2 GHzs)
2) Twice the L1 Data Cache (16 Kb compared to 8 Kb)
3) Larger L1 Trace Cache (16 Kb compared to 12 Kb)
4) Trace Cache Bandwidth (4 uOps/cycle vs 3uOps/cycle)
5) Twice the L2 Cache (1024 Kb compared to 512 Kb)
6) Better branch predictor (Better prefetch, higher IPC)
7) Lower Latency (Overall better performance)
8) Improved Hyperthreading (reduced collision of threads)
9) SSE3 (better performance in gaming, media, scientific apps)
10) Additional Write Combining Buffers

Their is also a good possibility of a faster system bus, the current P4 already have 800 mhz fsb, it probably be clocked at either 1066 mhz or 1200 mhz.
Who cares? AMD and Apple marketing hype will focus on just one point: their chips are 64 bits :rolleyes:

mathiasr

May 26, 2003, 03:04 AM

Originally posted by Cubeboy
Hyperthreading (Simultaneous Multi-Threading) follows the same general rules of dual processors (since it is essentially two processors except they share one set of integer-math, floating-math, SSE and code-decode units), the better threaded a application is, the greater the performance increase between a hyperthreaded processor and and it's non-hyperthreaded variant.
Here are some pages about the why and how of multithreading:
http://www.slcentral.com/articles/01/6/multithreading/index.php

SMT is not as efficiant as MP (multiple fullblown CPUs) nor CMP (multiple cores on the same die, often sharing L2+ caches).
It's rather a way to keep all execution units busy, and actually do something while some units wait on datas that are missing in L1 or L2 caches.

Cubeboy

May 26, 2003, 01:28 PM

Originally posted by mathiasr
Who cares? AMD and Apple marketing hype will focus on just one point: their chips are 64 bits :rolleyes:

Considering the arguments in this thread and others about the Prescott, quite a few people.

Cubeboy

May 26, 2003, 01:50 PM

Originally posted by mathiasr
Here are some pages about the why and how of multithreading:
http://www.slcentral.com/articles/01/6/multithreading/index.php

SMT is not as efficiant as MP (multiple fullblown CPUs) nor CMP (multiple cores on the same die, often sharing L2+ caches).
It's rather a way to keep all execution units busy, and actually do something while some units wait on datas that are missing in L1 or L2 caches.

No SMT is not as efficient, IBM estimates that at most, it can only be 80% as efficient as MP. From a architectural standpoint, Hyperthreading (SMT) is an parallel set of registers and logic to allow a pair of virtual processors to operate independently on a single chip. As I've mentioned before, this is like having 2 cores except they share the same cache and set of integer math, floating math, SSE and code-decode units (which would explain why it isn't as efficient as MP or CMP). Thats why we see hyperthreaded variants of the P4 listed with having 2 logical processors while older P4s without hyperthreading are listed with a single logical processor.