My criteria for upgrading is that the new machine must be a MINIMUM of 4 times faster. Do the Math. I have a G-5 Quad.
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Intel Nehalem Processor Details Leaked
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This is something that has always puzzled me.... I wont pretend I understand it fully but why have a 2.8GHz core if the bus is only 1.6ghz? You may as well have a 1.6Ghz core and save power right?!
Its great having all these core but why then force them to 'technically' run slower by cramming them through a slower bus. I dont get it?
Wouldnt a 1.6Ghz CPU with 1.6Ghz bus run just as fast, significantly cooler and use less energy than a 2.8Ghz CPU being forced through a 1.6Ghz bus?
Short answer: No. Because we have two levels of cache on the CPU side of the bus. The CPU never access RAM it only access the cache. The bus connects cache with RAM.
Longer answer:
Computer scientists use a term called "locality of reference", sometimes called "principle of locality" This means that a program references something at location A then there is a very good chance that the next thing it references will be located very close to A and not at some other random location. This principle i why a cache can work
We can take advantage of this if we design our computer to have a very small but fast local store to hold the data we are immediately using. We keep a litle more data very close at hand inside a very fast "L1" cache and more data is a slower L2 caches and finely we have RAM which holds most ifof the active data and this is finally backed by a disk drive that holds everything. The fastest store would be the registers inside the CPU. These work at fractions of a clock cycle. The disk is maybe a million times slower but also a billion times larger. the caches and RAm fill the space between
In practical terms here is an example. Lets say we have a simple bit of code that scans a string looking for the first slash character. If this code is ever executed it might run on average 20 times through the loop before it finds the slash. If the code is 30 bytes long then if it ran in RAM the CPU would have to pull 600 byes across the bus. But if it were loaded into L1 cache only 30 bytes are pulled from RAM but once they are there those 600 bytes can be read at "cpu speed"
One more angle: If we have a cache with access time A and a backing store with access time B what is the effective access time of the total system? It is the probability of the data being in cache times A plus probability of the data being in the backing store times B. If the "cache hit probability" is very high the system access time approaches A. In modern system the cache hit ratio is in the 90% range much of the time. Today we can't possibly afford to buy 4GB of L1 cache and I doubt it could be built at any cost. But we can have a memory system 90% as good be combining a cache with 4Gb of cheaper RAM.
My criteria for upgrading is that the new machine must be a MINIMUM of 4 times faster. Do the Math. I have a G-5 Quad.
Agreed! I just upgraded to 08 2.8 octo from G4 733
My criteria for upgrading is that the new machine must be a MINIMUM of 4 times faster. Do the Math. I have a G-5 Quad.
You have a good point. I've found that for a normal user setting at the keyboard doing real work, to notice the speed has to double. User can'tt notice a 1.5X increase, not unless they run tests and use a stopwatch. Human enses just work that way, sound has to almost doubt before we notic it's louder. (we notice 3dB but not 1) same with light camera f-stops are set to double or cut light by factor of 2 and skilled photographers can just light down to one f-stop. I guess this caries over to computers.
This is why it is so silly, these people holding out buying a computer waiting for 10% more CPU performance.
Got the message.
Penryn is now demoted to aged guano; only Nehalem is worthy of purchase.
All machines not equipped with Nehalem processors are now off the shopping list.
In the meantime, the Quicksilver (2002) keeps chugging happily along as it turns 6. Until it stops, or until I want to do something it just can't do, why replace it?
To any Apple people watching this page: the Mac Pro is too big. The iMac needs expansion (2 expresscard slots on the back would do fine). And the mini is too mini for outside the stereo cabinet. Although that hack to hotwire an external 3.5" SATA drive into the internal port looks pretty interesting. But still no 64-bit support, so it's hard to justify as a new machine.
Oh well;
Penryn is now demoted to aged guano; only Nehalem is worthy of purchase.
All machines not equipped with Nehalem processors are now off the shopping list.
In the meantime, the Quicksilver (2002) keeps chugging happily along as it turns 6. Until it stops, or until I want to do something it just can't do, why replace it?
To any Apple people watching this page: the Mac Pro is too big. The iMac needs expansion (2 expresscard slots on the back would do fine). And the mini is too mini for outside the stereo cabinet. Although that hack to hotwire an external 3.5" SATA drive into the internal port looks pretty interesting. But still no 64-bit support, so it's hard to justify as a new machine.
Oh well;
I went from a core 2 duo Dell E1405 Laptop with 2gb of ram. I notice the difference tremendously.
Penryn is now demoted to aged guano; only Nehalem is worthy of purchase.
All machines not equipped with Nehalem processors are now off the shopping list.
In the meantime, the Quicksilver (2002) keeps chugging happily along as it turns 6. Until it stops, or until I want to do something it just can't do, why replace it?
To any Apple people watching this page: the Mac Pro is too big. The iMac needs expansion (2 expresscard slots on the back would do fine). And the mini is too mini for outside the stereo cabinet. Although that hack to hotwire an external 3.5" SATA drive into the internal port looks pretty interesting. But still no 64-bit support, so it's hard to justify as a new machine.
Oh well;
Too big, have you lost your mind? It's too small if anything. The Mac Pro is perfect sized. Has enough room for everything a power user would like to have or have in the future.
8-cores w 8 GB RAM and 512 MB Graphics card just got to be fast enough for a while dammit.
I hope so too, just gone the same route!
I still laugh my ass off over that. Although I can't seem to decide which was worse; that thread or the thread when Apple first unveiled the iPod.
How ironic is it that Apple can piss off its fan base so much and then in the end actually grow in market share, profits, and popularity.
Power PC 4 evar!!! x86 sukz!!!1!1one|eleventy!!!
Thank you for your "contribution" to the discussion
If floating point performance is really that good, when is Intel going to stick a fork in Itanium? Development of that processor has been far, far below Intel's rosy projections when it was first introduced, and it has already done its job of killing off PA-RISC and MIPS. What I wouldn't give to see a MIPS R10k core running on Intel's current 45nm process; that would be a Godzilla of a CPU.
It'll be very impressive no doubt
I'll just enjoy my time with my "new" mac pro until it gets it's arse whooped in Q4
Ah well, I'm happy now.
I'll just enjoy my time with my "new" mac pro until it gets it's arse whooped in Q4
Ah well, I'm happy now.
Though I'd love to have a qhad core or oct core laptop I seriousley dont see this happening on a mac anytime soon. Im not haiting on the idea... the multi-tasking and speed boost would be insane.... I just dont think mac will divert from their slim design to conform to these humungo, power eating, hella-hot processors like Dell or Alienware or Voodoo laptops will. I mean look at the top "o" the line laptops today. They weigh like 10 or more pounds (Dell and other brands im refering to here).
Though in the end we WILL see this come to mac laptops I just dont think it'll be as soon as a year.. perhaps 2 or 3.
Now for the Mac Pro's and XServe I can see them implementing these newer processors with a new motherboard in a year or a year and a half but the price will be above 5,000.
hey i could be wrong but intel processors especially of this type will stasy high price ranged for awhile.
Though in the end we WILL see this come to mac laptops I just dont think it'll be as soon as a year.. perhaps 2 or 3.
Now for the Mac Pro's and XServe I can see them implementing these newer processors with a new motherboard in a year or a year and a half but the price will be above 5,000.
hey i could be wrong but intel processors especially of this type will stasy high price ranged for awhile.
New Mac Pro owners dont need to panic
I think if you have just bought an 8 core Mac Pro you will be fine for many years to come. Nehalem will bring some new innovations to the table but main improvement is the number of threads per CPU (Hyperthreading is back!) So a 2 socket, quad core processor will have 16 threads available to the OS. However, we all know that OSX and MOST apps are not capable of utilising this many CPU's, so there is nothing gained there. The other big improvement is in the memory subsystem, so apps which use high memory bandwidth (like audio and video) will see big performance improvements, esp. since the chipset will use DDR3.
However dont forget that in apps that move huge amounts of data around, the thing thats really holding you back is your hard drive. So no amount of extra CPU power or memory bandwidth will improve that. Faster drives (SSD, SAS, etc) will boost the speed that stuff gets done more than anything else (assuming you have enough memory)
Of course I am waiting for Nehalem because when I buy a Mac Pro I need it to last me a few years (and I cant afford one now anyway!) so I am a hypocrite but hey!
I think if you have just bought an 8 core Mac Pro you will be fine for many years to come. Nehalem will bring some new innovations to the table but main improvement is the number of threads per CPU (Hyperthreading is back!) So a 2 socket, quad core processor will have 16 threads available to the OS. However, we all know that OSX and MOST apps are not capable of utilising this many CPU's, so there is nothing gained there. The other big improvement is in the memory subsystem, so apps which use high memory bandwidth (like audio and video) will see big performance improvements, esp. since the chipset will use DDR3.
However dont forget that in apps that move huge amounts of data around, the thing thats really holding you back is your hard drive. So no amount of extra CPU power or memory bandwidth will improve that. Faster drives (SSD, SAS, etc) will boost the speed that stuff gets done more than anything else (assuming you have enough memory)
Of course I am waiting for Nehalem because when I buy a Mac Pro I need it to last me a few years (and I cant afford one now anyway!) so I am a hypocrite but hey!
Geshner I think its called. New architechure not due till 2011. Basically there will be a new CPU arch every 2 - 2.5 years, with a die shrink to a new process in between them. The new cpu arch brings new features and the die shrink brings faster speeds and lower power consumption.
What?
OMG! Am I the only one that cannot tell the difference between all the intel chips? I use to be able to tell by numbers or certain letters added to the numbers to tell the difference in chips but now.... in the humble words of spaceballs everywhere, we have reached "ludicrous speed".
OMG! Am I the only one that cannot tell the difference between all the intel chips? I use to be able to tell by numbers or certain letters added to the numbers to tell the difference in chips but now.... in the humble words of spaceballs everywhere, we have reached "ludicrous speed".
Great to know the timing. I'm considering a new desktop to augment my Macbook Santa Rosa and replace my iMac G4. Now I know that Nehlam is not going to be available before November 08 and maybe even later than that. I still think it will be in 08 because of Apple calling the current Pro the Early 08 Pro. Next we will have the late 08. So now I know that waiting doesn't mean waiting until the summer, but until much later than that.
Speed increase sounds nice, but if it comes with a big price increase (and it might), then maybe it won't be super compelling.
If I knew what was coming with the iMac (which is really enough computer for me), then I think I could really make an informed buying decision.
And frankly, in bang for the buck right now, a refresh of the displays is of pretty high concern to me. Maybe that happens today!
Speed increase sounds nice, but if it comes with a big price increase (and it might), then maybe it won't be super compelling.
If I knew what was coming with the iMac (which is really enough computer for me), then I think I could really make an informed buying decision.
And frankly, in bang for the buck right now, a refresh of the displays is of pretty high concern to me. Maybe that happens today!
Swagi posted this pic back in reply 40.
The gold blocks are new architectures, the red blocks are shrinks.
Also, check out http://en.wikipedia.org/wiki/Westmere_(CPU)#The_successor for more info...
Nehalem is a new micro architecture that will be used across the mobile, desktop, workstation, and low/mid-end server space.
True, but that's not what I asked. I was asking about the new system chipset that's the companion to Nehalem.