Scoobes said:
selnor said:
Scoobes said:
Do we know what the developers use PPE's for and how efficiently the 360's 3 cores are utilised? As far as I'm aware most of the power hungry stuff is shifted to the GPUs and in the PS3's case the SPEs. As far as I'm aware AI and physics are mainly covered on the CPUs but physics can also be done on the GPU and more efficiently, and I didn't think AI was particularly power hungry.
On PC I'm running on an AMD 3800 X2 (V.old) and games run fine whilst looking better than most console games as I'm running on an 8800GTS GPU.
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Compared to a modern personal computer, the relatively high overall floating point performance of a Cell processor seemingly dwarfs the abilities of the SIMD unit in desktop CPUs like the Pentium 4 and the Athlon 64. However, comparing only floating point abilities of a system is a one-dimensional and application-specific metric. Unlike a Cell processor, such desktop CPUs are more suited to the general purpose software usually run on personal computers. In addition to executing multiple instructions per clock, processors from Intel and AMD feature branch predictors. The Cell is designed to compensate for this with compiler assistance, in which prepare-to-branch instructions are created. For double-precision floating point operations, as sometimes used in personal computers and often used in scientific computing, Cell performance drops by an order of magnitude, but still reaches 20.8 GFLOPS ( Theoretical 1.8 GFLOPS per SPE, 6.4 GFLOPS per PPE). The PowerXCell 8i variant, which was specifically designed for double-precision, reaches 102.4 GFLOPS in double-precision calculations.
But from the tests we know An individual SPU on it's own has an actual GFLOP of 1.4 not 1.8. and further when using more together the efficiency decreases. as 8 SPU's only mnage 9.46 GFLOPS. Whereas 1.4 x 8 should be giving 11.2 GFLOPS not 9.46.
So as you can see, Sony through around the theoretical numbers of PS3 Cell. Didnt mention to their customers that it was based on 8 SPU Cell when the PS3 would only have 7 available with a further locked for Linux help. And then further forgot to mention that in real world terms it gets nowhere near 218GFLOPS.
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I'm actually more interested in knowing what and how developers actually use the CPUs as my current belief is that the CPUs on both consoles haven't really been utilised fully. What exactly do developers use the 3 cores and the SPUs on the HD consoles for and how efficiently are they being used?
And as for the numbers, MS and Sony love to throw out BS numbers to make their respective console sound good. Anyway they can think of to inflate the numbers to outdo the competition and say "My cock is much bigger than yours!". I think the lesson is to not listen to bullcrap PR.
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Yes. I understand that First Party Sony devs use SPU's to help out the inferiority in RSX. But then tha is taking away resources for CPU intensive tasks like, physics, AI and Cross edging. This is why it's always important to look at whole systems and never just one component.
