Skynet wants YOU!

[Sight Unseen]

Originally Posted by auroraglacialis

IIRC it started with Seti at Home, which I participated in, but that was in times when computer did not scale power consumption accoring to usage, so it reallz was a use of wasted cycles. These days, running this means to use more energy really. And if it comes to that I believe it is more energy efficient to let these things run on a specialized large computer than on many small systems. Besides, task management by priority does not always work best and there is also the issue of memory use and energy use. So for now I am not doing any of this. Maybe if they pay for the electricity they use, I will consider. Or if there are projects I relly like to support by a donation...

Maybe I can personally clarify the performance/Watt problem. I have a server that uses about 200W from the outlet and a desktop that uses about 550W. Both, in fact, have *extremely* similar architectures (Athlon II X2 vs Phenom II X6, same ram, same brand am3 mobos).

The desktop gets on average 25.2GFlops using 400W. (CPU only)
The server gets on average 11.2GFlops using 200W.
Desktop: 25.2/400 = .063GFlops/W
Server: 11.2/200 = .056GFlops/W

Although it's not that black and white. This both proves and disproves what you are saying. It is true that faster and more power-hungry systems (in this case, a 6-core 4.25GHz Phenom II X6) are actually more efficient than large numbers of slower systems (A dual core Athlon II X2 at 2.80 GHz). However, the argument that performance doesn't scale with power consumption is not always true. If I used 50 servers with the same spec, I'd still have the same performance/power ratio, because I'd use more power but also get more performance in a linear fashion. This is how most large computers are in fact constructed, with maybe 500 computers, each containing 2 or 4 CPUs. (With the exception of the IBM System z10, which fits somewhere in between a single box and a small supercomputer, with its 17 CPUs).