Recently, my computer screen keep flickering when starting up windows, but fine when in the Windows. However, the fickering will start again if i open some programes, especially games. Just now, my PC hang again. When i in bios, i was alerted that my +3.3Volt has droped. What is the problem? My graphic card's error? or my P.S.U. is failing? Btw, i m now currently using a 240 W PSU. I wonder can i just replace it with a higher power PSU. Will it cause any damge to my com? Thank You.