I have recently bought a silenx 400w PSU, and am concerned about the temperature. Im not sure if its faulty as it gets VERY hot. After 30 mins there is a lot of hot air coming from the rear fan. If I take the case of, the unit if also very hot. As the unit is sitting right by the CPU its putting at least an extra 8 to 10 degrees on the CPU I've e-mailed the supplier, but not yet had a response. How hot do PSUs normally run - should I be concerned?