Remember PA Semi? The company has just released, as promised, its first chipset. "They are full 64-bit PPC, support virtualisation, and would do Alitvec but that name is copyrighted by Freescale. Instead they do 'VMA'. The three parts run at a max wattage of 25, 15 and 10W for the 2.0, 1.5 and 1.0GHz parts respectively, with typical wattage listed at 13, 8 and 6W. The individual cores are said to have a 7W max and 4W typical power consumption at 2.0GHz." PA Semi was one of the prime reasons why Ars's John 'Hannibal' Stokes doubted Apple's reasoning for the switch to Intel.
To read all comments associated with this story, please click here.
Member since:2005-11-15
Member since:2005-07-06
These will have volume production in Q4, 2007, coinciding with Intel's 45nm Penryn CPUs. Penryn should debut at closer to 3 GHz than 2 GHz, with 2.66 GHz being a conservative estimate. At 2.66 GHz, Penryn should score about 2800 SPECint. Now, as the article points out, these PA Semi chips should score comparably to PPC 970 in SPECint, normalized by clockspeed. That puts a 2 GHz 1682M at a stunning... 1200 SPECint. This performance will almost be matched by Intel's ultra-low-voltage Core 2 coming out in Q2 which should get about 1150 SPECint at 1.08 GHz, with a TDP of 9W (1W typical).
SPEC 2000 benchmarks tend to show huge differences in performance between processors, SPEC 2006 and other benchmarks show these differences are nowhere near as big. Also, x86 have always been designed for integer performance first, nothing else is. The FP figures are the ones worth watching.
Anyway, it wasn't designed as a competitor to a high end desktop part, it would be best compared to laptop parts. That 25W figure includes a very potent NorthBridge. The best Intel parts currently use 35W, not including not including NorthBridge.
So, can we leave the "switch" talk aside, since its clearly ridiculous? This CPU is not and was not intended for an Apple notebook.
Apple were planning to use this processor at one point but then did the switch - which was not for technical reasons - I think the real reasons became obvious some time ago: Bootcamp and a big SRAM deal for the iPod.
Member since:2005-07-06
SPEC 2000 benchmarks tend to show huge differences in performance between processors, SPEC 2006 and other benchmarks show these differences are nowhere near as big
Well, since PA Semi only gave projected SPEC 2000 figures, I worked with what I had. I'd be interested to see SPEC 2006 benchmarks for these processors. And other benchmarks can show even bigger differences. GCC compilation, for example, absolutely flies on x86. x86's tend to have highly-optimized memory systems, since they have so few registers, and that gives them a big boost in code that deals with heavily-indirect data structures (graphs, trees).
Also, x86 have always been designed for integer performance first, nothing else is. The FP figures are the ones worth watching.
x86's are designed for integer performance because that's the most important thing in the desktop/workstation space. And that's the crucial point here: nothing else is designed for the desktop/workstation space. And no, FP figures aren't worth watching, because nobody cares about FP performance on a laptop. People only barely care about FP on the desktop, and will only care less about FP as more of that code is outsourced to the GPU.
Anyway, it wasn't designed as a competitor to a high end desktop part, it would be best compared to laptop parts.
Those are laptop parts! Even shipping laptop parts embarrass the PA-Semi chip (again, in laptop-relevant metrics). All this talk about bootcamp and SRAM is a cop-out. The simple fact is that the x86 world has the best laptop/desktop/workstation CPUs, period.
Edited 2007-02-06 02:07
Member since:2005-08-09
Member since:
2005-07-06
These will have volume production in Q4, 2007, coinciding with Intel's 45nm Penryn CPUs. Penryn should debut at closer to 3 GHz than 2 GHz, with 2.66 GHz being a conservative estimate. At 2.66 GHz, Penryn should score about 2800 SPECint. Now, as the article points out, these PA Semi chips should score comparably to PPC 970 in SPECint, normalized by clockspeed. That puts a 2 GHz 1682M at a stunning... 1200 SPECint. This performance will almost be matched by Intel's ultra-low-voltage Core 2 coming out in Q2 which should get about 1150 SPECint at 1.08 GHz, with a TDP of 9W (1W typical).
So, can we leave the "switch" talk aside, since its clearly ridiculous? This CPU is not and was not intended for an Apple notebook. It's got some seriously interesting features like on-die 10 gigabit ethernet, integrated PCI-Express, and a mesh inter-processor communications mechanism. It's a very interesting chip... if you're building a router or a supercomputer.