I've been reading the posts and just thought I would throw my 0.0006369
BTC regarding temps, psu and hash speed...
I use 1 HP Common Slot 1200W Server PSU with a Gigampz BB per SP20. I'm not concerned with noise and power is cheap. I am guessing that the spikes in the "last day" chart is the SP trying to auto correct for the PSU but I'm not sure. If anyone has some thoughts I'd welcome them.

try backing down the .77 to .75 yeah you may stay at 1600 but more stable show us this page
see all of mine are 85c due to under clock if you have a lot of 120 or 125c you are just a bit too much overclocked
