As of a few days ago, my power supply as started spinning at full speed. Every 45 - 60 seconds the fan will spin at full speed for approx. 10 seconds, then slow back down to normal. It started happening one morning when I turned on my PC. Nothing in my system or its surroundings have changed. This is really confusing me. It's a relatively new PSU (6 months) so I'm not too sure what's causing it. Its an EVGA Supernova Nex 650G. Any ideas?