selnor said:
READ THIS. IT'S OBJECTIVE, HAS PROOF FROM IBM THEMSELVES AND WELL ACTUAL PROOF RATHER THAN SPECULATION. BECAUSE NUMBERS GET THROWN AROUND AND PEOPLE SEEM TO FORGET THE REALITY OF HOW THE PS3 and 360 WORK AS A WHOLE INCLUDING THE OS USAGE.
Here's proof that the ps3's so called Cell advantage is very misleading by Sony:
According to IBM’s white pages, the cell processor being used in the ps3 is considerably less powerful than what it has been hyped up to be.
Sony officially revealed the PS3 and for the first time at E3 2005, and claimed that their Cell processor would be capable of 200 GFLOPS.
One may wonder how they got that figure? IBM's own white pages:
http://www-128.ibm.com/developerworks/power/library/pa-cellperf/?ca=drs-#table4
As seen from the link (in Figure 5) the Cell has a theoretical peak of 201 GFLOP’s– running 8 SPE’s at 25.12 GFLOP’s apiece (Table 2). This is where Sony gets their 200 GFLOP figure from.
When physically tested however for theoretical peak performance, only 155.5 GFLOP’s were actually achieved (see Table 4) with a total efficiency rate of 75.9%.
Because of manufacturing yield issues, the PS3 only uses 7 SPE’s with the theoretical peak for the PS3’s Cell processor being reduced to 176 GFLOP’s, each running at 25.12 GFLOP’s. Utilizing the same 75.9% efficiency, it is easily interpolated that the PS3’s Cell CPU will only be capable of 133.6 GFLOP’s.
The Xbox 360 has 3 general-purpose 2-threaded CPU's, which generates a proven 115.2 GFLOP’s which is dramatically easier for developers to utilize. By now it should be pathetically obvious that sony is no where near as far ahead as they try to lead you to think (keep in mind they claimed that the ps2 was more powerful than the original xbox, but were proven wrong publicly, since the xbox was indeed twice as powerful). The ps3 will, once you have taken into account thetotal amount of resources that will be used by their respective operating systems, end up with less CPU power available for graphical and physics processing than the 360.
http://ps3.qj.net/Inside-the-PS3-s-Operating-System-/pg/49/aid/21047
According to the (unbiased) site above, the PS3 will also constantly reserve 1 SPE** for running its operating system. Now that there is actually one less SPE reserved for gaming purposes, it is definite that the ps3’s cell will only be capable of 114.4 GFLOP’s for the purpose of game processing.
**SPE’s are floating point processors, they are also called DSP’s, and SPU’s. These floating point processors are NOT to be confused with cores, cores have far more prediction and calculation braches than floating point processors. As stated earlier, the 360 has 3 cores, each running at 3.2GHz, with 2 threads each. The cell also runs at 3.2GHz, but is the one and only core that the ps3 has.
Back to subject:
The 360’s OS on the other hand uses only 3% of its CPU time on Cores 1 and 2, while Core 0 is free altogether, and 6.25% (32mb) of its 512mb RAM, this means that the 360 has more processing power available for in-game graphics and physics. Meanwhile, the ps3’s OS…
“In the case of the PS3 this equates to 12.5% of the available Cores on the CPU always reserved, an additional 12.5% sometimes taken by the OS, 12.5% of the available RSX memory and 25% of XDR Cell memory. Balancing these out, one could argue that Sony has removed up to 25% of the available CPU power and 18.75% of RAM for these features as well as others that are not mentioned here or will be added in future updates to the PS3 Operation System.”
Wow, 18.75% (96mb) of the ps3’s 512mb of total RAM, vs. 6.25% (32mb) of the 360’s 512mb RAM, say, that means the ps3 has 416mb RAM left vs. the 360’s leftover 490mb RAM for graphics…
I could be wrong, but isn’t 490mb greater than 416mb???
Sources:
http://arstechnica.com/news.ars/post/20060413-6600.html
http://ps3.qj.net/Inside-the-PS3-s-Operating-System-/pg/49/aid/21047
Now, the GPU (Graphics Processing unit). The 360’s Xenos GPU is also slightly more powerful for running current graphics engines and, in terms of complying with Windows Graphic Foundation 2.0 (compatible with future versions of Direct X, shader models, etc.) is a full-generation ahead of the RSX. "One of the key ideas behind a unified architecture is to move the GPU from a rendering only processor to a complete compute processor. Right now all the GPU does is render 3D and displays it on your screen (yes it does more like 2D, video etc... but for the point of this article we are talking about 3D). With a unified architecture the GPU becomes more. It becomes a processor that can do almost anything that needs code processed. This means the GPU can take on more functions like physics, AI, animation and many other processes that can benefit the gaming experience. DirectX 10 and a unified GPU architecture helps a video card become an all-in-one Swiss army knife of game processing. Those are the ideas at least, how it all works out is up to the game content developers"
http://enthusiast.hardocp.com/article.html?art=MTA0NSwzLCxoZW50aHVzaWFzdA. According to this article, the unified memory of the 360 and the unified shaders, developers have the ability to use the vector processing power of the GPU, which is a big plus as it allows the developer to use the shaders when they need extra processing power.
Sony could be in a lot of trouble considering the ps3 is much more expensive than its superior rival that is using long proven technology, while the ps3 is using technology that still has yet to be proven, and has been giving sony one problem after another, causing game delays.
"However, using Sony's claim <***>, 7 dot products per cycle * 3.2 GHz = 22.4 billion dot products per second for the CPU. That leaves 51 - 22.4 = 28.6 billion dot products per second that are left over for the GPU. That leaves 28.6 billion dot products per second / 550 MHz = 52 GPU ALU ops per clock.
*** Using sony's own claim against it. If sony really didnt make this claim, they most certainly would have taken legal action against MS, that is only fact.
It is important to note that if the RSX ALUs are similar to the GeForce 6800 ALUs then they work on vector4s, while the Xbox 360 GPU ALUs work on vector5s. The total programmable GPU floating point performance for the PS3 would be 52 ALU ops * 4 floats per op *2 (madd) * 550 MHz = 228.8GFLOPS which is less than the Xbox 360's 48 ALU ops * 5 floats per op * 2 (madd) * 500 MHz= 240 GFLOPS."
ps3 GPU stands at 228.8 GFLOPS
360 GPU stands at 240.0 GFLOPS
I have shown actual evidence and provided easy to follow logic.
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