Intel Xeon Processors
With all the past history of Risc chips being better than Cisc in the matter of instruction sets, why is Apple not going with an Intel version of them? Aren't Intel Xeon and Itanium processors Risc chips? Both of Intel's RISC current Ghz rating about the same as the PPC. Is this a matter of Risc hitting the wall, or just the PPC?
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Originally posted by geobe
With all the past history of Risc chips being better than Cisc in the matter of instruction sets, why is Apple not going with an Intel version of them? Aren't Intel Xeon and Itanium processors Risc chips? Both of Intel's RISC current Ghz rating about the same as the PPC. Is this a matter of Risc hitting the wall, or just the PPC?
Apple realizes power consumption verses performance is the only thing that matters.
While the rest of the world has in the recent past been moving towards hot running chips with expensive support systems, Apple has kept their systems cheaper to build and more reliable by using cool chips.
Suddenly the Pentium M is the coolest running and lowest power chip around, it uses 1/4 the power of those other chips -- I just read that in an article somewhere a good source would be nice.
Originally posted by Existence
The Xeon is just a beefier version of the Pentium 4 with more cache, support for ECC and better hyperthreading support. Apple will likely use future versions of the Xeon based on Conroe/Merom/pentium M in its PowerMacs and Xserves.
I can't believe you started this thread. I just came here to start a thread similar to this, but with more details. I think I'm still going to.
Originally posted by geobe
With all the past history of Risc chips being better than Cisc in the matter of instruction sets, why is Apple not going with an Intel version of them? Aren't Intel Xeon and Itanium processors Risc chips? Both of Intel's RISC current Ghz rating about the same as the PPC. Is this a matter of Risc hitting the wall, or just the PPC?
Actually, I don't think either chip is considered RISC. The Xeon uses the same x86 ISA that the P4 uses. As other users have pointed out, it will likely find its way into Apple's server machines.
Officially, Itanium is neither RISC nor CISC... it's something Intel has termed "EPIC", which stands for Explicitly Parallel Instruction-set Computing (or something like that). I'm cribbing from an Ars* article I read on the subject ages ago and am too lazy to look up right now so I don't remember exactly what sets EPIC apart. IIRC it puts a lot of the burden of scheduling instructions on the compiler instead of the processor. Other than that, I don't know much about it. It could be that EPIC is just a marketing term for "the good parts of RISC + the good parts of CISC".
I don't think RISC has "hit a wall". In fact, if you read any Ars* article on the architecture of the more recent Pentiums (III, 4, and M), you'll see that they refer to them as "RISC-like". Modern Pentiums decode x86 instructions into smaller instructions called micro-ops. If you think about it, breaking complex instructions into simpler ones is what RISC is all about. It's just that an x86 chip does it on the CPU at run time and a RISC chip expects it to be done by the compiler.
* Pardon the Ars whoring
Originally posted by geobe
Is this a matter of Risc hitting the wall, or just the PPC?
RISC didn't hit a wall, IBM and FreeScale just decided they aren't interesting in competing with Intel in the notebook/desktop market spaces. Processor development comes down to how much money you can spend on it. PPC vs. x86 probably gives the PPC guys a (very) small advantage in terms of how many dollars you have to spend to design a processor of a given performance/watt level... unfortunately this PPC advantage is nowhere near sufficient to make up for the (at least) 25-to-1 ratio in sales. The PowerPC 970 came about because IBM had already done most of the development for its POWER4 servers, but it turned out that this just doesn't scale down to notebook-level power levels. FreeScale's efforts in the embedded space simply don't scale up to notebook levels comparable to the Pentium-M anymore. Apple doesn't have the resources to drive chip development just for itself, and it is much cheaper for them to migrate to x86.
The Itanium IA-64 architecture has nowhere near the performance/watt required for Apple's needs, and doesn't match Intel's x86 integer performance numbers (although IA-64's floating point numbers are pretty good).
The leaves Intel's x86 chips (or AMD's) as the only potential choice for Apple to use, and it guarantees that Intel's huge R&D budget is never going to beat Apple's new chips.
Originally posted by elron
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Officially, Itanium is neither RISC nor CISC... it's something Intel has termed "EPIC", which stands for Explicitly Parallel Instruction-set Computing (or something like that). I'm cribbing from an Ars* article I read on the subject ages ago and am too lazy to look up right now so I don't remember exactly what sets EPIC apart. IIRC it puts a lot of the burden of scheduling instructions on the compiler instead of the processor. Other than that, I don't know much about it. It could be that EPIC is just a marketing term for "the good parts of RISC + the good parts of CISC".
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IA-64 (Itanium) is largely the Hewlett-Packard Precision Architecture (HP-PA) RISC chip set and the x86 ISA reduced to a single chip. Intel coined the acronym EPIC to avoid using the acronym RISC.
Originally posted by MACchine
Suddenly the Pentium M is the coolest running and lowest power chip around, it uses 1/4 the power of those other chips -- I just read that in an article somewhere a good source would be nice.
In this article you will see that a Pentium M can beat or run on par with some very high powered Intel chips, while consuming ~27W, the other were running around 115W and 30 to 40W in idle mode.
http://www.tomshardware.com/cpu/2005...ntium4-01.html
This is why Apple is going to Intel, chips on this road map are the future for Apple.
Originally posted by Brendon
In this article you will see that a Pentium M can beat or run on par with some very high powered Intel chips, while consuming ~27W, the other were running around 115W and 30 to 40W in idle mode.
http://www.tomshardware.com/cpu/2005...ntium4-01.html
This is why Apple is going to Intel, chips on this road map are the future for Apple.
Thanks, here is another article...
http://www.eweek.com/article2/0,1759,1825776,00.asp
Originally posted by MACchine
Thanks, here is another article...
http://www.eweek.com/article2/0,1759,1825776,00.asp
Thanks
Users, and Apple continually pitted the PM up against the Dual Xeon, and various AMD processors as it's equal, or lesser adversary on the x86 side.
Is Apple still committed to delivering this level of performance to their pro user base?