CrazzyMan said: i will write here some facts:
1) about POWER of RSX:
RSX 5 shader ALU operations per pipeline per cycle (2 vector4 and 2 scalar (dual/co-issue) and fog ALU) 27 FLOPS per pipeline per cycle 68 billion shader operations per second theoretical maximum ( ((5 ALU x 24 pixel pipelines) + (2 ALU x 8 vetrex pipelines)) x 500 MHz ) 364 GFLOPS ( ((27 FLOPS x 24 pixel pipelines) + (10 FLOPS x 8 vertex pipelines)) x 500 MHz ) 24 filtered and 32 unfiltered texture samples per clock Maximum polygon count: 333.3 million polygons per second (in HS RSX _alone_ 3MT = 90MT/s)
Xenos 2 shader ALU operations per pipeline per cycle (1 vector4 and 1 scalar, co-issued) 10 FLOPS per pipeline per cycle 48 billion shader operations per second theoretical maximum (2 ALU x 48 shader pipelines x 500 MHz) 240 GFLOPS (10 FLOPS x 48 shader pipelines x 500 MHz) 16 filtered and 16 unfiltered texture samples per clock Maximum polygon count: 500 million triangles per second (in DR _with cpu_ only 4MT per frame with 30fps = ~120MT/s, 4 times less) http://forum.beyond3d.com/showthread.php?t=31532&page=3
2) Aand about RSX and Cell:
[...] Regarding cpu, yes its totally different arguments. The 360's is a very standard setup, a bunch of cores that can all see main memory. The advantage to this is that lots of thread coded written over the years can be ported to it easily. For example, Valve (the Half Life guys) are writing an entirely threaded engine for the PC. When it's done, porting it to the 360 will be easy. How about porting it to the PS3? Nope, won't work, it's a totally different setup. The PS3's main core is basically the same, but its spu's can't see main memory. Each one has 256k that it can work with, so you need to rewrite your code to pack things into 256k chunks, feed it to the spu's to process it, then copy it all back to main memory. In other words, you've gotta rewrite your code.
Now before I get jumped on here let me briefly mention the downsides. The 360's cpu setup is painfully easy to code for. But, they really aren't all that fast. Worse yet, all three cores use the same memory controller so the three cores are not three times the power of the one core on the PS3 due to some overhead. The PS3's spu's on the other hand are monstrously fast. You need to setup your data correctly to work with them, but once thats done then yes, the 360's cpu setup is crap compared to fully working spu's. I say fully working because most current games out there barely even touch on them, it will take time to re-write everything. I haven't done spu coding....yet. I will be though in 2007 which will be pretty cool.
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First of all, I found it funny that you highlighted the numbers which are better on the RSX but didn't do so in the opposite case. You can see what I'm talking about highlighted in yellow in the quote above (regarding triangles per second).
Now for some facts that you have forgotten:
- You can't compare shader operations per second directly, because the 360 uses a unified shading pipeline rather than separate pipelines for pixels and vertices. This means that pixel and vertex operations don't have to wait for each other, and the pipeline can run at 100% efficiency. That's something to take into account when looking at peak performance numbers, which will never be attained in the PS3 when looking at real-life code.
- The 360 has additional power that you haven't mentioned, in the form of the 10 MB's of EDRAM that can do anti-aliasing with no performance hit in certain resolutions, and with a small performance hit in bigger resolutions. Anti-aliasing is something that I haven't seen in PS3 games, at least not decent anti-aliasing for sure, as anyone can verify by seeing PS3 game screenshots.
Regarding your comment that "once thats done then yes, the 360's cpu setup is crap compared to fully working spu's", we are again looking at a pipe dream. Not all tasks will be easy or possible to implement using 256 KB chunks of memory, and that data shuffling that you're talking about also has its overhead. It's funny that you mention overheads of the 360's architecture all the time, but conveniently forget the Cell's shortcomings when it comes to programming ease and generality, which it's lacking on...