Why is my PC apparently frying video cards?

This morning my video card just stopped working (there was bad weather but power never went out). I tested the monitor on another pc which worked so I went out and bought a new video card. I put it in a different slot and it worked for about 5 minutes. Right after I changed my display settings, the computer froze and I had to do a hard reboot. When I powered back up the new video card wasn't working either. Any ideas on what could be causing this? I haven't had the PC up long enough to see if anything else is wrong with it. Any help would be greatly appreciated. Thanks|||Aaaaaa, ahev you UNinstalled the OLD vidoe drivers, SHUTDOWN computer and then installed the drivers for the NEW card?|||before you do anything, make sure the fans on the power supply are working properly

if they arent, your system could be baking and frying video cards

this happened to me at school once

nice system (celeron 3GHZ, 1GB RAM, GeForce 6600LE) nearly died because the fan just stopped working

but we caught it in time and saved it



the method varies for fan sizes:

80MM fans (the ones you can see from the back)

just turn it on with the case off, shine a light through the holes inside the inside of the case, then look through the fan

if you see the fan spinning, its working

if not, turn it off and buy a new power supply



for 120MM fans (on the inside of the power supply, taking up the whole bottom of the unit's cover):

same as before, but shine the light from the outside and look inside|||Assuming the heat sink and fan on your processor is working, and any fans on your video cards are working, I'd check the power supply.

They are notorious for making hardware woes hard to track down.|||What happens when you take the old video card out and put it in another machine? Does it still work?