Wbmw:
Sure you are lying because the EE C2Q CPU power usage didn't include the chipset, VRMs, 2GB DDR3/1600 memory and all the other stuff on the MB running 3DMark06 HDR/SM3.0 in software. That is the CPU on its "board". They didn't look at just the 2 R770 GPUs, they looked at all that was on the GPU board's total power.
Absolute power is meaningless unless you look at performance too. The CPU running 3DMark06 HDR/SM3.0 in software uses way more power than a 790GX IGP with a 1GHz Sempron running the same thing and it performs far slower than the 790GX IGP to boot. That is a big condemnation against EE C2Q CPUs being used for GPU loads. Does it do better with CPU loads? Doesn't matter as GPUs and their loads were being dicussed.
Besides given the performance, that test is still CPU bound with the 4870x2 as the the tests showed that it does far better relative to the GTX280 at 2560x1600 than at the tested 1600x1200. Perhaps both power usages would have been higher, but the performance per watt would have been higher for the 4870x2. Most of the game tests by all the reviewers showed that the 4870x2 really didn't stretch its lead until resolutions went to 2560x1600, where many times it was the only one to produce playable frame rates.
If you've looked at the last few generations of GPUs, they've all been increasing the high end power envelope in order to push the performance bar higher. That's not a sustainable strategy, no matter how much performance it can deliver.
If you have looked at the last few generations of CPUs, they've all been increasing the high power envelope in order to push the performance bar higher. That's not a sustainable strategy, no matter how much performance it can deliver.
While it's true that the CPU is not going to run 3DMark06 as well as a GPU, it's also true that the GPU won't run the majority of general purpose applications as well as the CPU. The CPU is the only general purpose processor in the system, no matter what nVidia and ATI marketing would like you to believe. Amdahl's Law works for the GPU, just as it does for the CPU.
But the 4870x2 will only be used for GPU and GPGPU work, read HPC of very parallel loads. They don't check highly serial loads that push against Amdahl's Law. In that area the EE C2Q doesn't do well either given its high power usage. It loses against a fast single core Athlon 64 using far less power because of the high latency to memory of FSB attached chipset memory.
Like I originally stated, we were talking about GPUs and their loads, not GP CPU work. That is your red herring or irrelevancy. In the GPU area, GPUs are the correct tools for the job. Even for highly parallel loads like typically found in the HPC area. There a 2.4Tflops processor even at 300W is quite efficient in a Tflops per watt basis. Even the 1Tflops GTX280 is efficient, just not as high. The 25.6Gflops EE C2Q is nowhere even close at over 200W (all using SP). The CPU gets a little higher when DP is used with the 4870x2 getting 480Gflops below 300W, the GTX280 getting 100Gflops below 200W and the EE C2Q getting 12.8Gflops over 200W still far behind.
The well used engineering rule is "use the right tool for the job." For GPU loads, that is the GPU. In the HPC area, it depends on just what the task is. But I suspect many will move to the GPGPUs as they deliver Tflops class performances for under $1K and under 1KW usage. The CPUs will be more used for control than HPC application work because they are better at it. Long term, I don't know whether loosely coupled (attached on die APUs) or strongly coupled (VPUs alongside FPUs inside CPU cores) will win out. I suspect that loosely coupled will win over the short (<4 years) and medium term (5-10 years) and strongly coupled with take over slowly after that in areas that APUs are used nearly always.
As for useful performance of GPUs, I think that the growth will slow, but much more slowly than CPU performance growth will over time. The resolution and polygon counts needs to climb quite a bit, but as time has shown, that grows rather faster than tasks do. APUs for graphics, construction (flesh out trees, buildings, etc.), physics, collision detection, simulation, etc. will continue to take loads off the CPU during games to add realism while taking into account the slow growth in available GP CPU performance. We are a long way from artifact free virtual worlds that we can interact both visually and aurally without disbelief rearing its ugly head and tainting our enjoyment. We have come a long way though from the early days of Pong or more recently, Castle Wolfenstein.
Pete
