Re: GTX260 PSU and Hear Concerns
1. Not sure what the amp draw of the 260 is. What model is your PSU?
2. My cards crash when temps get over 80*C, but that's with them overclocked. I would say up to 70*C is as high as you'd want them to be getting. With the fans set at 55%, mine don't go passed 60*C and idle at 40*C ish.
3. I use Everest for monitoring all temps.