None. And I was stressing a 75GXP pretty heavily for 2 years, and powered on 24/7. It was from the Hungarian plant too, and with no active cooling, close to other heat-producing components like the CPU and video card, and near the back of the case with no rear exhaust fan except the one on a 3 year old Antec PSU on a single fan design (no intake fan on the bottom). It got a bit loud before I ended up retiring it, but I never even developed bad sectors.