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arn
Aug 7, 2002, 08:59 AM
MacBidouille (http://www.hardmac.com/niouzcontenu.php?date=2002-08-07#3189) (temporarily house at http://www.hardmac.com) posted a graphic from an American RAM Distributed which advertises DDR Ram for XServe and the New PowerMac.

Of note, it lists rates of 266Mhz and 333Mhz, while the XServe only supports 266Mhz DDR RAM.

Now, more often than not, ads such as these from 3rd party vendors represent educated guesses by the vendors than any true leaks.

big
Aug 7, 2002, 09:05 AM
WOW! 333 mhz ram! that would so ROCK!

Ensign Paris
Aug 7, 2002, 09:11 AM
Coupled with X.2 and a faster G4, 333mhz DDR would be a huge jump in performance.

I would love to see them even if my schedule doesn't allow me to replace my main mac for another year ;)

Ensign

big
Aug 7, 2002, 09:23 AM
Yep...I gotta wait at least a year also

Mr. Anderson
Aug 7, 2002, 09:24 AM
Its a step in the right direction - why is waiting until next week and the possible new machines starting to get me all excited, even though I too won't be buying anything soon.

topicolo
Aug 7, 2002, 09:35 AM
I'm hoping so too, but from what I'm seeing on the PC side, a fsb and ram upgrade will only get you so far. When AMD switched to DDR ram, there was only a 3-5% increase. When AMD switched to 333Mhz DDR RAM, there was another 2-3% increase. That's only a total increase of about 5-8% maybe less if you consider that the G4 has had a L3 cache helping it along all this way

SubFredZero
Aug 7, 2002, 09:40 AM
333 DDR.... that's gonna kost big bucks. I would like to be able to buy a powermac in the futur but with these prices.... :s

agreenster
Aug 7, 2002, 09:45 AM
But isnt DDR ram yesterdays news? RD Ram is where its at, isnt it? It still feels like Apple is still behind the technology forefront.

If Apple wants to move heavily into the film/studio/post effects department, (which it seems like they do with Maya 4.5 coming out and their recent purchase of Shake...) they need to up their performance level beyond DDR ram.

tjwett
Aug 7, 2002, 09:50 AM
DDR shmee-DR. yawn. BFD. the XServe doesn't even have true DDR support with it's fsb still at 133. for true DDR use you need the bus and the RAM. don't worry, Apple is still way behind;)

ImAlwaysRight
Aug 7, 2002, 10:03 AM
Originally posted by Ensign Paris
I would love to see them even if my schedule doesn't allow me to replace my main mac for another year
Not me. I sold my old Mac a week before MacWorld NY and got top dollar and will buy whatever new PowerMac Apple releases. My money is sitting in the bank just waiting to be spent. 333MHz DDR would be nice... just as long as it offers a lot MORE SPEED!!!!!!

HalimC
Aug 7, 2002, 10:05 AM
Originally posted by agreenster
But isnt DDR ram yesterdays news? RD Ram is where its at, isnt it? It still feels like Apple is still behind the technology forefront.

If Apple wants to move heavily into the film/studio/post effects department, (which it seems like they do with Maya 4.5 coming out and their recent purchase of Shake...) they need to up their performance level beyond DDR ram.

RDRAM is the main competitor to DDR. RDRAM is a proprietary technology developed by Rambus and Intel. It is more expensive, and Rambus itself is an evil company that uses sleazy patents to extort money out of other memory makers like a parasite. Rambus needs to die the slow painful death it deserves. DDR is the way to go, and the way Apple will go.

This article has some more information: http://www.hardwarecentral.com/hardwarecentral/reports/1519/6/

Rocketman
Aug 7, 2002, 10:09 AM
Originally posted by big
Yep...I gotta wait at least a year also

You may have no choice. Assuming a 8-24-02 release date and with the relatively huge pent-up demand for a major new motherboard scheme, initial release may result in a multi-month order backlog.

If you are not one of these folks that place their orders on release day/week, you will likely be waiting 1-3 months to see a system. Rarely does delivery actually happen in less than a month anyway.

The iPod 20 shipped this week and was announced at MW for example.

Whether the MB is 266 memory or 333 the problem will be the same. The lurking question is the native speed of the bus. Lots of people have put off Tower purchases to avoid crippled 133 mhz FSB.

If that suits you, you might as well buy a eMac or iMac and get cool features at a very low price.

That reminds me, everyone buy a friend or relative an eMac. They are dirt cheap.

Rocketman

jg3
Aug 7, 2002, 10:09 AM
Originally posted by topicolo
I'm hoping so too, but from what I'm seeing on the PC side, a fsb and ram upgrade will only get you so far. When AMD switched to DDR ram, there was only a 3-5% increase. When AMD switched to 333Mhz DDR RAM, there was another 2-3% increase. That's only a total increase of about 5-8% maybe less if you consider that the G4 has had a L3 cache helping it along all this way

I think (and hope) you are wrong. If you are, this will prove that G4's really are very much more powerful than x86 chips. You see, if you take a spigot and hook a garden hose up to it, you will get a good stream of water coming out the end of the hose. If you hook the same hose up to a fire hydrant, the result will be about the same. BUT if you put a fire hose on a spigot, you will get the same flow as you did with the garden hose... whereas putting a fire hose on a fire hydrant makes a big difference. Come on, DDR!!

Rocketman
Aug 7, 2002, 10:18 AM
Originally posted by ImAlwaysRight

Not me. I sold my old Mac a week before MacWorld NY and got top dollar and will buy whatever new PowerMac Apple releases. MORE SPEED!!!!!!

What are you posting on? A PC? A IIsi? :)

Rocketman

SubFredZero
Aug 7, 2002, 10:32 AM
Originally posted by Rocketman


That reminds me, everyone buy a friend or relative an eMac. They are dirt cheap.

Rocketman

What are you, a miljonair ?

DaveGee
Aug 7, 2002, 10:33 AM
Originally posted by agreenster
But isnt DDR ram yesterdays news? RD Ram is where its at, isnt it? It still feels like Apple is still behind the technology forefront.

If Apple wants to move heavily into the film/studio/post effects department, (which it seems like they do with Maya 4.5 coming out and their recent purchase of Shake...) they need to up their performance level beyond DDR ram.

Any chance you know the reason WHY 'Apple is still behind'? I take it you don't otherwise you would have instead stated "MOTOROLA and their crappy G4 CPU is still behind the technology forefront"... :rolleyes:

Apple can't give us something if the MOTOROLA G4 will not support it... Well they can but then you have the xServe.... DDR is used by just about EVERYTHING ***BUT*** the MOTOROLA G4 CPU!

The G4 intro'd in Aug 99 @ 500Mhz and 850MB/s of memory bandwith support (SDR) THREE FULL YEARS later and what has MOTOROLA added to the G4? 500Mhz of speed AND that's about it... Bahhh MOT has done more to hurt Apple over the past three years than any other company I can think of...

MOT RANT OFF (for now) :)

Dave

topicolo
Aug 7, 2002, 11:03 AM
Originally posted by jg3


I think (and hope) you are wrong. If you are, this will prove that G4's really are very much more powerful than x86 chips. You see, if you take a spigot and hook a garden hose up to it, you will get a good stream of water coming out the end of the hose. If you hook the same hose up to a fire hydrant, the result will be about the same. BUT if you put a fire hose on a spigot, you will get the same flow as you did with the garden hose... whereas putting a fire hose on a fire hydrant makes a big difference. Come on, DDR!!

That's assuming that there will be a constant flow of water coming out of the spigot or the fire hydrant. In real world usage, (to use your spigot analogy), the water will be coming out in bursts. A fatter pipe will assure that the bursts come out quicker, but if there's nothing coming, it won't do any good. In most office applications, you probably won't see much of a difference in the new architecture. In games, there'll probably be a noticeable increase (maybe more in the order of 10% faster than a similar Mhz old-school G4). But most of the performance will probably occur in science and high-level graphics apps.

sturm375
Aug 7, 2002, 11:12 AM
Originally posted by agreenster
But isnt DDR ram yesterdays news? RD Ram is where its at, isnt it? It still feels like Apple is still behind the technology forefront.

If Apple wants to move heavily into the film/studio/post effects department, (which it seems like they do with Maya 4.5 coming out and their recent purchase of Shake...) they need to up their performance level beyond DDR ram.

You have it backwards. RD (RamBus) is yesterday's news. It has almost reached the highest speed it is able to , and is currently being out paced by Motherboards with DDR333. Now, there is a few source for DDR400, and the testing shows that it blows the doors off any RamBus, and they don't think RamBus can catch it.

Some Technical details:
It's been a while but I think these are the specifics behind the tech. DDR RAM is 128-bit wide bus, while RamBus is 8 or 16-bit. RamBus gets it's speed the Intel way, more Mhz, while DDR increased the number of things done in a cycle.

In the PC world, it is not uncommon to find someone buying DDR333 for a system that accepts upto DDR266. What they are doing is overclocking. While I don't think people will be overclocking an Xserve, I wouldn't be suprised to see people buying faster RAM on the false premise that it will improve preformance. Also since the manufacture of the RAM doesn't cost much more to make DDR266, or DDR333, It's all profit for the vendor.

jelloshotsrule
Aug 7, 2002, 11:36 AM
Originally posted by dukestreet
Its a step in the right direction - why is waiting until next week and the possible new machines starting to get me all excited, even though I too won't be buying anything soon.

quite simple.... the better the new models are, the better the models or two after them will be... thus, the better the computer you end up getting will be.... word?

agreenster
Aug 7, 2002, 12:12 PM
Thanx guys, my last comment was more in the form of a question than a bold statement (if you didnt notice)

Im anxious to see how this all pans out. If DDR is the way to go, then good for them. But I still see faster processors (and structure altogether) in high-end IBM Workstations and SGI boxes (with higher price tags too, of course). Thats what Apple needs to overcome if they want to push into the high end markets.

I guess this is off-subject, and should be in another forum altogether, but Apple seems to be really trying to push into the 3D realm; however, they need to seriously have a power-house workstation in order to compel 3d hobbyists, students, schools, and studios to switch from IBM/SGI/Sun.

Apple has:

1. Unix (nice UI too)
2. XServe (for rendering)
3. Maya 4.5 (soon)
4. Shake

Apple Doesnt have:

1. A Workstation comparible to an SGI Fuel box or IBM RS/6000 44P 270

2. Renderman for OSX (I assume we can look forward to this)

Pants
Aug 7, 2002, 12:32 PM
Originally posted by sturm375


You have it backwards. RD (RamBus) is yesterday's news. It has almost reached the highest speed it is able to , and is currently being out paced by Motherboards with DDR333. Now, there is a few source for DDR400, and the testing shows that it blows the doors off any RamBus, and they don't think RamBus can catch it.

Some Technical details:
It's been a while but I think these are the specifics behind the tech. DDR RAM is 128-bit wide bus, while RamBus is 8 or 16-bit. RamBus gets it's speed the Intel way, more Mhz, while DDR increased the number of things done in a cycle.

In the PC world, it is not uncommon to find someone buying DDR333 for a system that accepts upto DDR266. What they are doing is overclocking. While I don't think people will be overclocking an Xserve, I wouldn't be suprised to see people buying faster RAM on the false premise that it will improve preformance. Also since the manufacture of the RAM doesn't cost much more to make DDR266, or DDR333, It's all profit for the vendor.

ahem.
http://www17.tomshardware.com/mainboard/02q2/020501/

theres reaons NOT to buy rdram,but its nothing to do with performance OR price for the top end gear... its merely horses for courses and thats basically it....

(as topicolo said, fudging ddr onto a slow bus hardly makes a chip scream, and judging by my athlon, ddr hardly makes a noticeable difference)

ImAlwaysRight
Aug 7, 2002, 12:55 PM
Originally posted by Rocketman


You may have no choice. Assuming a 8-24-02 release date and with the relatively huge pent-up demand for a major new motherboard scheme, initial release may result in a multi-month order backlog.

If you are not one of these folks that place their orders on release day/week, you will likely be waiting 1-3 months to see a system. Rarely does delivery actually happen in less than a month anyway.

The iPod 20 shipped this week and was announced at MW for example.

The PowerMac 1GHz announced Jan 31, '02 also shipped the same day. I don't see why new PowerMacs won't be shipping when announced. Apple certainly doesn't need to wait until Jaguar ships on 8-24 to ship the new PowerMac. The production of system CD's for the PowerMac should be a lot faster than retail boxes with Jaguar skin on them.

Unless Apple isn't finished with the new PowerMac yet. But, I'm hoping they are in production right now. Woooo-hooooo!

ImAlwaysRight
Aug 7, 2002, 12:59 PM
Originally posted by Rocketman


What are you posting on? A PC? A IIsi? :)

Rocketman

Actually, a G4 iMac 800 at work. I want a better/faster system at home for the work I do there. Work is just text/email/web stuff. So the iMac is fine there and looks rather cool on my desk. Awesome that I only need one power cable for CPU/monitor/speakers running to my desk (which sits in the middle of my office).

At home I am without a Mac right now. But I sold my iMac G4 800 w/15" screen just before the 17" was announced, and good thing, too. I actually made money on the deal, so even though my cable internet at home is unused for 1-2 months, it still all works out.

Bring on the new PowerMacs!

rugby
Aug 7, 2002, 01:07 PM
I too am getting antsy and this year I can afford to buy a new computer! Yay me, maybe I'll get a new 20gb iPod and give this old 5gb one to my wife.

adelaney
Aug 7, 2002, 01:29 PM
Originally posted by jg3


You see, if you take a spigot and hook a garden hose up to it, you will get a good stream of water coming out the end of the hose. If you hook the same hose up to a fire hydrant, the result will be about the same.

I'm thinking that if you put a garden hose on a fire hydrant something very different would happen. :)

luiss
Aug 7, 2002, 02:57 PM
This would go nicely with the nForce2 rumors. True, nForce2 can support DDR400, but DDR400 RAM is not as cost effective as DDR333 at the moment.

Sun Baked
Aug 7, 2002, 03:06 PM
Intel is still keeping RDRAM limping along, but have DDR options available across most of the chipset line.

Sort of a huge mistep on Intel's part, to design the P4 and chipsets for RDRAM and then continuously have it be beaten back by one bad press release after another.

All the while Rambus struggles to survive and avoid bankruptcy, while the lawyers continue to suck the Rambus dry over the patent spat.

I guess this attempt to corner the memory market could be called a dismal failure, but it's not over yet.

Chryx
Aug 7, 2002, 03:09 PM
Originally posted by agreenster
But isnt DDR ram yesterdays news? RD Ram is where its at, isnt it?

Actually, it's "Swings and roundabouts"

RDram is high bandwidth, high latency, DDR ram is medium bandwidth, low latency, most of the time latency is more critical than bandwidth.

For most purposes IMHO, DDR ram (possibly in a 128bit/dual channel configuration like Nvidia's Nforce chipset) is a better solution that RDram


Intel are phasing out RDram by the way, Their new server chipset is DDR based, and they have no new Rambus chipsets on their roadmap.

Chryx
Aug 7, 2002, 03:14 PM
Originally posted by sturm375

It's been a while but I think these are the specifics behind the tech. DDR RAM is 128-bit wide bus, while RamBus is 8 or 16-bit. RamBus gets it's speed the Intel way, more Mhz, while DDR increased the number of things done in a cycle.


DDR ram is 64bits wide
RDram is 16bit, but typically clocked a LOT higher (and it also uses DDR tech)

16bitx400Mhz DDR = 1.6GB/s = PC800 Rdram

64bitx100Mhz DDR = 1.6GB/s PC1600 DDR

Of course, RDram is typically dual channel (giving 3.2GB/s of bandwidth to a processor that can use it, which in the consumer market right now is basically the P4)

Sun Baked
Aug 7, 2002, 03:16 PM
Originally posted by Chryx
Intel are phasing out RDram by the way, Their new server chipset is DDR based, and they have no new Rambus chipsets on their roadmap.

Cool ...

Wonder how long it'll take Rambus to implode as RDRAM is phased out of the workstation and server market.

TechKid
Aug 7, 2002, 03:17 PM
Yeah, every one knows about DDR on the new Macs... Whether it's 333 or 400 or even 266 will increase speed but I don't see that as being anything spectacular. DDR has been around for a while and finally moto has included support. What will be interesting is if Apple includes Serial ATA. If they do, they'll be the first major computer supplier that includes it and as I'm told, they'll have a 6 month jump on Dell and the like. Apple has been using ATA 66 (which is just as old as 133 SDRAM) for a long time.

I think I'm just wishful thinking because Seagate(?) just came out with the first retail serial ATA drive.

Hud0
Aug 7, 2002, 03:26 PM
Originally posted by topicolo
I'm hoping so too, but from what I'm seeing on the PC side, a fsb and ram upgrade will only get you so far. When AMD switched to DDR ram, there was only a 3-5% increase. When AMD switched to 333Mhz DDR RAM, there was another 2-3% increase. That's only a total increase of about 5-8% maybe less if you consider that the G4 has had a L3 cache helping it along all this way

Actually, with AMD's first DDR chipset you saw about a 10% increase (see www.anandtech.com) then with VIA's KT266A (133 Mhz-->266 DDR) you saw anywhere from a 10% to even as much as a 48% improvements over SDRAM. But with VIA's KT266 (original DDR solution, no A,) you saw little or no improvement with DDR. So it would appear that if done correctly DDR can give you at least a 10% improvement in scores, or if it's just a hack can have little or no effect.

Also, when you say AMD switch to 333 Mhz, the Front Side Bus is still at 133 (266 DDR,) only the memory is running at 166 (333.)
This is with VIA's chipset. We have yet to see synchronous FSB and memory at 333Mhz, without overclocking that is.

dongmin
Aug 7, 2002, 03:57 PM
Originally posted by agreenster
Im anxious to see how this all pans out. If DDR is the way to go, then good for them. But I still see faster processors (and structure altogether) in high-end IBM Workstations and SGI boxes (with higher price tags too, of course). Thats what Apple needs to overcome if they want to push into the high end markets.

I guess this is off-subject, and should be in another forum altogether, but Apple seems to be really trying to push into the 3D realm; however, they need to seriously have a power-house workstation in order to compel 3d hobbyists, students, schools, and studios to switch from IBM/SGI/Sun.


Since when are "hobbyists, students, [and] schools" using high-end servers from IBM and Sun to do their 3D homework?

And I don't think Apple is trying to go toe to toe with IBM or Sun. Why would they want to?

iwantanewmac
Aug 7, 2002, 04:12 PM
Originally posted by tjwett
DDR shmee-DR. yawn. BFD. the XServe doesn't even have true DDR support with it's fsb still at 133. for true DDR use you need the bus and the RAM. don't worry, Apple is still way behind;)


As always..... sigh :(

ktlx
Aug 7, 2002, 04:29 PM
Originally posted by sturm375

Some Technical details:
It's been a while but I think these are the specifics behind the tech. DDR RAM is 128-bit wide bus, while RamBus is 8 or 16-bit. RamBus gets it's speed the Intel way, more Mhz, while DDR increased the number of things done in a cycle.


This is not exactly correct. Both DDR 266 and RDRAM 1066 have the same clock rate, 133Mhz. The difference between the two is what is going on during that clock rate. DDR accesses memory twice during the clock cycle (once up and once down, hence double data rate) while RDRAM accesses memory four times during the clock cycle (twice up and twice down, hence quad pumped). The 1066 comes because there are two channels (133 * 4 * 2 ~ 1066). Similarly the older RDRAM 800 had a 100Mhz clock rate (100 * 4 * 2 = 800).

Since the current G4s have a SDR 133Mhz FSB, there is questionable value to DDR 333 memory beyond the ooohhh factor. If the new G4s have a 166Mhz FSB then DDR 333 will be valuable if the memory controller is able to feed both processors or the FSB can do DDR like the AMD Athlons can.

I guess we will find out in a week or so.:D

ktlx
Aug 7, 2002, 04:35 PM
Originally posted by Sun Baked
Wonder how long it'll take Rambus to implode as RDRAM is phased out of the workstation and server market.

RDRAM never did catch on in the server market. Early on the memory was too expensive and by the time the prices dropped, DDR RAM was nearly as fast and a safer bet. 1GB of RDRAM for a server would cost more than any other component in the system (unless you had a RAID array). Once Intel makes a good DDR 400 capable chipset and the supply is there, RDRAM will be about as common as EDO memory.:D

Chryx
Aug 7, 2002, 05:30 PM
Originally posted by ktlx
This is not exactly correct. Both DDR 266 and RDRAM 1066 have the same clock rate, 133Mhz. The difference between the two is what is going on during that clock rate. DDR accesses memory twice during the clock cycle (once up and once down, hence double data rate) while RDRAM accesses memory four times during the clock cycle (twice up and twice down, hence quad pumped). The 1066 comes because there are two channels (133 * 4 * 2 ~ 1066). Similarly the older RDRAM 800 had a 100Mhz clock rate (100 * 4 * 2 = 800).


Um, no?

PC1066 is 16bits wide, 533Mhz Double Data rate, giving 2.1GB/s, but Rdram is typically deployed in a dual channel configuration giving 4.2GB/s total bandwidth (which lines up nicely with a Pentium 4B's 533Mhz - 4.2GB/s FSB)

The Pentium 4's frontside bus otoh, DOES run at 133Mhz x 4 transfers per clock

cyberfunk
Aug 7, 2002, 06:27 PM
Will someone with some smarts please answer said question that I've been asking for a while:

When the new Pmacs come w/ "DDR Ram" how will we know weather thats just DDR to chipset (like Xserve) or DDR to chipset to CPU, that yeilds the truely high performance ? what should I look for to determine the answer to this question?

Thanks

Rocketman
Aug 7, 2002, 07:11 PM
Originally posted by cyberfunk
Will someone with some smarts please answer said question that I've been asking for a while:

When the new Pmacs come w/ "DDR Ram" how will we know weather thats just DDR to chipset (like Xserve) or DDR to chipset to CPU, that yeilds the truely high performance ? what should I look for to determine the answer to this question?

Thanks

There's got to be a downloadable utility somewhere to test this. It woldn't have to be really complicated and better yet it could be native unix.

Rocketman

ktlx
Aug 7, 2002, 07:34 PM
Originally posted by Chryx


Um, no?

PC1066 is 16bits wide, 533Mhz Double Data rate, giving 2.1GB/s, but Rdram is typically deployed in a dual channel configuration giving 4.2GB/s total bandwidth (which lines up nicely with a Pentium 4B's 533Mhz - 4.2GB/s FSB)

The Pentium 4's frontside bus otoh, DOES run at 133Mhz x 4 transfers per clock

Are you sure? I have read several places that describe RDRAM as sampling two up and two down and not one up and one down. But then again, thinking about it, I am not sure if they references I have are describing what is going on in the RIMMs.

barkmonster
Aug 7, 2002, 07:39 PM
I would love to see them even if my schedule doesn't allow me to replace my main mac for another year

Same here, It just seems like I'd have a lot more options if there we're more powerful macs to start with. 1Ghz or above with DDR on the entry level seem worth the wait to me. I've got no hope of buying a new mac this year but summer of next year wouldn't be a problem and by then who know's what we'll get for 1,300 or so.

Chryx
Aug 7, 2002, 07:44 PM
Originally posted by ktlx
Are you sure? I have read several places that describe RDRAM as sampling two up and two down and not one up and one down.

Yes, I'm quite sure.

Rdram is clocked at half it's PCxxx rating, and uses DDR signaling. but it's narrower, so it can be clocked higher without clock skew problems (which affect wider interfaces.. like 64bit SDram :)

slaboda
Aug 7, 2002, 08:12 PM
Originally posted by dongmin


Since when are "hobbyists, students, [and] schools" using high-end servers from IBM and Sun to do their 3D homework?

And I don't think Apple is trying to go toe to toe with IBM or Sun. Why would they want to?

Dongmin, I agree. What Apple needs to do is get OS X running on IBM's PowerPC servers. Then they'll have an enterprise solution with relatively little investment compared to trying to keep up with the big boys in the server market, which they've proven they can't do.

Bear
Aug 7, 2002, 09:21 PM
Originally posted by slaboda


Dongmin, I agree. What Apple needs to do is get OS X running on IBM's PowerPC servers. Then they'll have an enterprise solution with relatively little investment compared to trying to keep up with the big boys in the server market, which they've proven they can't do.

Or maybe for the high end server market, they should consider porting Max OS X to SPARC. Which would give it a full range of Sun systems to run on.

billiam0878
Aug 7, 2002, 10:11 PM
I don't know much about this, but wouldn't Apple need to up their system bus to 166MHz (necessitating a large motherboard remodeling) to use 333MHz DDR RAM? 333MHz would be nice, but I imagine we'll just see 266.

Bill

ibookin'
Aug 7, 2002, 11:39 PM
Originally posted by billiam0878
I don't know much about this, but wouldn't Apple need to up their system bus to 166MHz (necessitating a large motherboard remodeling) to use 333MHz DDR RAM? 333MHz would be nice, but I imagine we'll just see 266.

Bill

Apple needs a 166MHz bus anyway to compete with the likes of ASUS, Tyan, etc.

I hope they do. Come on, Daddy needs a new Tower!

cyberfunk
Aug 8, 2002, 12:57 AM
Originally posted by Rocketman


There's got to be a downloadable utility somewhere to test this. It woldn't have to be really complicated and better yet it could be native unix.

Rocketman



I dont think it's that easy.. plus, it'd be nicer if I knew what to look for on the motherboard, like if there were tell tale signs ? obviously there is a big performance boost, but I want to know if it's coming form a DDR to chipset to CPU bus thats wide open !!!??

HumanJHawkins
Aug 10, 2002, 12:01 AM
In addition to my Mac uses, I also build custom Windows systems. In the custom build and overclocking world, advertisement and use of ram beyond the official specs for a motherboard is common.

I hate to rain on everyone's parade, but this is just a vendor attempting to attract the kind of customer who either thinks that more is better even if the machine can't make use of it (there are a lot of these customers by the way) or the customer who wants to try to fiddle with the motherboard to make it run faster than rated.

For an example of this, consider two things:
1) There are currently no DDR based motherboards, Mac or Wintel (WinAMD) that support faster than PC 2700 (333 MHz DDR)
2) You can go to www.pricewatch.com right now and see dozens of vendors selling 366, 400, and even 433 MHz DDR memory (which you could also put in your XServe if you wanted, though it would only run at 266 MHz while installed there).

Is this because someone on the Windows side of the fence is going to put out a 433 MHz capable motherboard soon? No... Just because some people want to go overboard.

FYI about memory, you can put faster memory of the same type into your computer... It just won't run any faster than what your computer is rated for without some serious tweaks.

bousozoku
Aug 10, 2002, 12:32 PM
Originally posted by tjwett
DDR shmee-DR. yawn. BFD. the XServe doesn't even have true DDR support with it's fsb still at 133. for true DDR use you need the bus and the RAM. don't worry, Apple is still way behind;)

DDR--double data rate RAM uses the leading and trailing edges for transfer. So, its speed is double whatever the memory bus speed is. 133(.33) x 2 = 266(.66). 166(.66) x 2 = 333(.32) 200 x 2 = 400. That is true DDR.

tjwett
Aug 10, 2002, 04:45 PM
Originally posted by bousozoku


DDR--double data rate RAM uses the leading and trailing edges for transfer. So, its speed is double whatever the memory bus speed is. 133(.33) x 2 = 266(.66). 166(.66) x 2 = 333(.32) 200 x 2 = 400. That is true DDR.

i meant, don't you need a DDR bus though? correct me if i'm wrong.

Sun Baked
Aug 10, 2002, 05:17 PM
This is what people think is happening with the XServe the Bus and DDR ...

barkmonster
Aug 10, 2002, 05:47 PM
Barefeats (http://www.barefeats.com/pentium4.html) have just updated their "G4 vs Athlon vs Pentium 4" page. Not only is the Xserve beaten by a 1.6Ghz Athlon in every test but it's beaten by the dual Ghz G4 tower in some of them aswell, only managing to match it rather show any improvements you might expect from it's DDR RAM. I know it's still just a 133Mhz FSB and the DDR is there to provide bandwidth for the drives and networking, not for the CPU but you'd think there'd at least be a tiny improvement over the tower.

Let's just hope we get a real DDR version of the G4 not some hack of a chipset like the xServe uses on the new towers when they're out. Most benchmarks seem to show an 8 - 10% improvement over PC133 when DDR266 is used, with the G4 having a lower clock speed than an athlon or Pentium 4 but a fairly high IPC rating, DDR would really benefit a G4.

The 1GHz G4 in the test has a 133Mhz FSB, 256K L2, 2Mb L3 and SDRAM, it's between 20% slower and 26% faster than a 2Ghz Pentium 4. Assuming the Pentium 4 is the 2000A northwood model it's got a 100Mhz FSB x 4, 512K L2, no L3 and 800Mhz RDRAM yet it's only managing to push out the effective performance of a 1.266Mhz G4 assuming the G4 was the same kind and on the same motherboard as the 1Ghz G4.

Here's the pentium 4 I assume is used in the test :

2Ghz (Northwood 2000A)
512K L2 @ 2Ghz : SRAM - (100% of clock speed)
100Mhz x 4 FSB : RDRAM (40% of clock speed)

The dual Ghz G4 used in the test :

1Ghz - (PPC7455 / Apollo)
512K L2 @ 1Ghz : SRAM - (100% of clock speed)
2Mb L3 @ 250Mhz x 2 : DDR - (50% of clock speed, 4:1 ratio x 2)
133Mhz FSB : SDRAM (13.3% of clock speed)

here's how I see DDR would benefit a G4 using the rumoured specs of the new G4 :

1.4Ghz - (actually 1.4166 Ghz because of the FSB speed)
512K L2 @ 1.4Ghz : SRAM - (100% of clock speed)
2Mb L3 @ 354Mhz x 2 : DDR - (50% of clock speed, 4:1 ratio x 2)
166Mhz x 2 FSB : DDR (23.5 % of clock speed)

It would still be below the Pentium 4 as far as how much slower the main system RAM runs when compared with CPU but baring in mind how much damage a 1Ghz G4 with SDRAM does to the 2Ghz Northwood, I can only imagine what sort of results we'd see pitting a G4 with the above specs against a Northwood. Given the fact the G4 has to work a lot less than a Pentium 4 to get the same or better results we're in for a real treat when we finally get DDR on the mac.

It's just the whole idea of it being as useless as the Xserve as far as performance is concerned, you can't really feed a 1Ghz chip enough with 133Mhz SDRAM as it is, if it still only pushed 133Mhz of bandwidth from the RAM to the CPU on a 1.4Ghz G4 it really would be a waste of potential power.