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Old 2007-01-01, 18:19   #2
Joe O
 
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Aug 2002

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While I think that the Xbox 360 is a much better processor, it appears that the PS3 CELL BE is much more widely accessable. Yes, there is now a "free" development system available for the Xbox 360. But I think you have to pay to get the key to allow you to load it on the Xbox 360.
The Xbox 360 is also a "Cell" PPC based processor. It has 3 fully capable processors, instead of one fully capable and 7 or 8 crippled ones. More info can be found here with more detail here.
For those of you who have been around long enough, or just have studied CPU history, the PS3 CELL BE is is roughly the design of the CDC 6400. Oh, you never heard of the CDC 6400? You never heard of CDC? I wonder why.
The Cell BE is also available from Mercury Computer Systems, Inc. I don't know prices. The only reason to buy the PS3 from Sony is if they really do lose money on each sale.
Yes, the PSP Cell processor can do Double Precision FP calculations, but not as fast as the SP rates that are usually quoted.
Quote:
Thus for computationally intense algorithms like dense
matrix multiply (GEMM), we expect SP implementations to
run near peak whereas DP versions would drop to approximately
one fourteenth the peak SP flop rate [10]. Similarly,
for bandwidth intensive applications such as sparse matrix
vector multiplication (SpMV) we expect SP versions to be
between 1.5x and 4x as fast as DP, depending on density
and uniformity.
from The Potential of the Cell Processor
for Scientific Computing
Samuel Williams, John Shalf, Leonid Oliker
Shoaib Kamil, Parry Husbands, Katherine Yelick
Computational Research Division
Lawrence Berkeley National Laboratory
Berkeley, CA 94720

Quote:
Re: does spu-gcc support altivec insturction set
Originally posted: 2006 Nov 22 01:36 PM
Dan_Greenberg Post new reply

The PPU includes a VMX (AltiVec) unit, so it's not surprising that your code compiles using the ppu-gcc compiler. Remember, the stand-alone PPU is a fully compliant Power Architecture processor.

As the previous post says, an SPU is not a VMX unit. It's similar in many ways, but it's not code compatible. One key difference is that a VMX unit is not an independent thread whereas an SPU is. Another is that the VMX unit "sees" memory as the PPU does, while the SPU sees its local store only, with DMA access to the rest of memory. Intrinsics may help you port, if your original code was written that way. Certainly, your experience with AltiVec in general will give you a leg up on structuring and optimizing your SPU code.
from the IBM forum

Last, but not least, here http://www.cellperformance.com/artic...ps3_linux.html is a good place to start for putting *nix on your PS3
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