[QUOTE="04dcarraher"][QUOTE="super600"]
I know the cpu will be slow compared to the 360's cpu but it will obviously be stronger then the 360's CPU.I except a decent leap over this gen, but not an oh my god leap like this gen.
gamecubepad
I doubt they will go below 3ghz, AMD APU's ie A10 5800k only has a TDP of 100w, and that's including a 3.8 ghz cpu with a IGP. 7660. So a plain CPU would be like 50w TDP.. Also a quad core bulldozer at 3.8 ghz would be well over 3x the processing power. Interesting excerpt from a DF interview with 4A'sOles Shishkovstov:
Digital Foundry: How would you characterise the combination of Xenos and Xenon compared to the traditional x86/GPU combo on PC? Surely on the face of it, Xbox 360 is lacking a lot of power compared to today's entry-level "enthusiast" PC hardware?
Oles Shishkovstov: You can calculate it like this: each 360 CPU core is approximately a quarter of the same-frequency Nehalem (i7) core. Add in approximately 1.5 times better performance because of the second, shared thread for 360 and around 1.3 times for Nehalem, multiply by three cores and you get around 70 to 85 per cent of a single modern CPU core on generic (but multi-threaded) code.
Bear in mind though that the above calculation will not work in the case where the code is properly vectorised. In that case 360 can actually exceed PC on a per-thread per-clock basis. So, is it enough? Nope, there is no CPU in the world that is enough for games!
The 360 GPU is a different beast. Compared to today's high-end hardware it is 5-10 times slower depending on what you do. But performance of hardware is only one side of equation. Because we as programmers can optimise for the specific GPU we can reach nearly 100 per cent utilisation of all the sub-units. That's just not possible on a PC.
In addition to this we can do dirty MSAA tricks, like treating some surfaces as multi-sampled (for example hi-stencil masking the light-influence does that), or rendering multi-sampled shadow maps, and then sampling correct sub-pixel values because we know exactly what pattern and what positions sub-samples have, etc. So, it's not directly comparable.
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This, along with geometry and texture LOD is the essence of console optimization.
Depends on vector instructions e.g. barrel shifter on Xbox 360's PPE is very slow. The above statement wouldn't be applicable for 256bit wide AVX SIMD era Intel Sandybridge.
http://forum.doom9.org/archive/index.php/t-157701.html
"The Cell is a pretty slow CPU. It takes roughly 2.5 cores (out of 8) to do realtime 1080p H.264 decoding with a highly optimized decoder. A fast i7 can do that with about ~0.4 cores (out of 4 or 6)."
PowerPC ISA doesn't have advantage of FMA/FMAC over AMD Bulldozer/Piledriver.
On HPC's CPU side, there's a reason why the world's fastest supercomputer is powered by AMD Bulldozer. AMD Bulldozer/Piledriver can handle 4 operands FMA/FMAC while PowerPC/SPU ISA only handles 3 operands FMA/FMAC.
AMD Bulldozer was designed to be heavy multi-threaded floating point monster for the CPU side i.e. it's 8 core has 8 128bit wide FMAC/FMA (with FMA3 and FMA4) i.e. it's AMD's own CELL like solution from AMD's CPU team. This is not factoring AMD's APU team.
Intel gets FMA3 support with Intel Haswell.
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