Playstation 3: An Under Rated System

[CrazzyMan]

NJ5 said:

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.

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...

1) today, shader operations are more important, then polygon count. You should know that.

2) In Lost Planet, each character is 10-20K polys. A VS robot is 30-40K polys. A background is about 500K. With shadows and other hidden rendering cost, it's about 3 million polys per frame.
Now..I can't see how RSX, if used in the right way, should be so limited at vertex processing: in HS we easily render 2-2.5 MTriangles per frame at 30 fps without being VS limited and without making any use of CELL to speed up vertex shading and I know for sure that being more clever we could even go faster..(just using the GPU)

The numbers quoted about HS are slighty wrong..cause a few days a go I realized there's a bug in the code that computes the triangle count: in some cases it's more close to 3M triangles per frame mark than 2M.

Do you understand, that RSX by itself doing better then x360 GPU+CPU ???

3) yeah? let`s speak about jaggies in geow or forza2(a LOT of jaggies) ? While in Heavenly sword will be 720p 4xAA and HDR. And do you see jaggies in Ratchet ?

4) Q: "Ten years ago, Final Fantasy VII became a symbol to the entire PlayStation format. Could FFXIII come to mean as much for the PS3?"

A:"FFVII was a milestone in PS history. The game changed the entire RPG genre and set a lot of new trends. Strictly content-wise, the theme alternated between fantasy and futurism and we're doing something similar with FFXIII. The game mixes a new kind of fantasy with futuristic elements that have never been seen in a game before. It's very interesting to explore the new hardware. When you've managed to harness the power in it the results become unbelievable. We're accomplishing things you hardly can manage without the PS3."
http://www.neogaf.com/forum/showthread.php?t=159861