I tweaked the cards a bit to guarantee their temps stayed below 75 celcius and the rig ran fine overnight.
If any one of the cards rises above 85-90 for too long though this seems to happen :S
I thought GPUs were smart enough to automatically shut off after getting too hot?!
What GPU's are they? When I first got mine and they were pushing 80 C I started getting worried about temps so I searched for it and from what I found, most 5850's internal cutoff doesn't trigger until 100 C or more even though it is generally recommended to keep them below 80 C.
They are 5870s, from all different manufacturers.