When i play games for a long period of time my monitor will turn to ping and green colums with pink, green, and blue pixel blocks within the colums. The mouse locks, comp locks and the power button wont turn the comp off; i have to use the power supply switch to turn the thing off. upon restarting it seems fine until i try and play the game again and it flips out and goes to the fairy screen again, 3rd try its fine nothing happens plays fine. couple days later it locks with the colums again. this has happened 8 times since 2 weeks ago. I've been told my video card and/or my agp slot is going out. I need help. Plz hurry.