I've posted this in a couple of hardware forums before, but didn't get much answer...

A few days ago, I read about this guy's folding farm: http://www.overclock.net/overclock-net-folding-home-team/370859-nitteo-s-f-h-gpu2-farm.html. While it's a great effort (and I applaud him that), it's very resource consuming. The guy probably pays $400-500 for electricity every month.

After reading that, I had some discussions on building a more efficient folding system (and farms). Through your experiences, which hardware setup do you find is more efficient? Perhaps an Atom-powered system with multiple GPUs folding (even on PCI slots)? or is PS3 still the best current hardware for folding?

Does anyone know how much faster folding in PS3 is compared to modern GPUs? Also, which one consumes more energy (assuming the GPU is placed in a medium-end PC).

The discussion isn't just BOINC-specific, can also apply to folding@home, or other services... since BOINC doesn't fully support PS3 and GPU folding yet outside of PS3GRID project.