Xenon and Revolution CPU's

[Panajev2001a]

it will have a higher sustained flop rating than the cell chip in the ps3 will have

???

Both get their performance from VMX-style units, from parallel processing using custom SIMD Vector Units...

What is your reasoning behind that statement ?

The efficiency of SPU in PSOne ?

I seriously think you are again downplaying Sony hadware way too much.

 

[DeanoC]

[

Probably a silly ? but what is ISA

I'm guessing Industry Standard Architecture or Instruction Standard/Set Architecture.

Thanks, BTW they can do a totaly new CPU to this right ISA ,i.e. , a clean sheet design, Right?

Absolutely.

But sometimes an ISA can be a problem to do an efficient design as certain instruction can only be done using slower methods.

This happened on POWER, they removed certain instruction that made supercalar processing much harder. The cleaned modern version would be called PowerPC.

The other way of mantaining compatibility is simple not to bother supporting these instruction directly. In most older ISAs, modern processors do some instructions via microcoding, these are 'emulated' in the processor. Are generally much slower but mantain compatibilty. Things like the old string instructions in x86 (they have even older providence going back to the 8080 processor).

 

[pc999]

Thank you very much.

 

[MrSingh]

it will have a higher sustained flop rating than the cell chip in the ps3 will have

???

Both get their performance from VMX-style units, from parallel processing using custom SIMD Vector Units...

What is your reasoning behind that statement ?

The efficiency of SPU in PSOne ?

I seriously think you are again downplaying Sony hadware way too much.

sorry pana, you know it's going to be NV30 all over again!!!

merry xmas!

 

[Megadrive1988]

I have little doubt that the PS3 CPU will have a higher peak flops performance as well as a higher sustained flop performance than Xenon's CPU. no reason not to think so, at this point. unless Cell and PS3-CPU is some sort of massive disaster, which is pretty unlikely, even if it doesn't reach the lofty levels that have been 'floating' around no pun intended

 

[Wunderchu]

I have little doubt that the PS3 CPU will have a higher peak flops performance as well as a higher sustained flop performance than Xenon's CPU. no reason not to think so, at this point. unless Cell and PS3-CPU is some sort of massive disaster, which is pretty unlikely, even if it doesn't reach the lofty levels that have been 'floating' around no pun intended

I agree

 

[one]

Or if you're in IBM, the chance to start a processor design with a clean sheet of paper does come often, every time IBM accepts an offer from a game console maker?

Getting nervous about the Xe CPU and its potential realworld performance numbers? Let me wipe that sweat from your brow, Merry X-mas.

"potential" and "realworld" sound mutually-exclusive to me

XeCPU's ISA will be compatible with PPC970 or a subset of PowerPC instructions just like RISC-oriented POWER4 (from which PPC 970 was derived) ISA, plus SIMD units backward compatible with AltiVec. Why I assume it compatible with AltiVec is because without it you can't test optimization on Power Mac G5 devkits. If the compiler can take care of everything and Xenon developers don't have to care too much about its platform, devkits could be x86 Windows systems but actually Mac were used. (Well Microsoft might want it as a beta-test of Windows PPC kernel but who knows) Except for AltiVec just trimming compatibility-related things from PPC970 can give it performance gain. In addition to ISA, you can cut little-endian support and 32-bit support. But I don't call such a treatment a "clean sheet design".

Gekko for the GameCube lacks AltiVec but has Write Gather Pipe, a data compression function and a floating point pipeline, but it's still not called a "clean sheet design" AFAIK.