@Acill

I have used one for years without any problems whatsoever. Back in the days of RC5 I had the computer going 24/7 crunching keys, even during the warmest summer days. I also have a big fan (at really low RPM) inside the case, just to secure a constant airflow in the case past the CPU card, since I also have a low-noise PSU with fans that never starts (possibly due to the low Wattage of the Pegasos).