video locks pc
 

ok, just installed mplayer today.....after i installed everything was fine.....then a little while later i went to open a .avi file and the picuture had like green, blue, very choopy just looked horrible, then after a few seconds it locked my pc and i had to hit the power button to reboot.....i kept trying, must of locked my pc 10 times, then just a little while ago its fine again.....also when it was happening i checked a another video in the player in the kde browser and same thing, so its not the mplayer, that was the reason i looked for a different player because of that (bad pic, locking pc) but thought it was just the kde player doing it, btw, i tried all kinds of .avi,.mpg, etc. files to see if maybe it was just a certain file, but all the same. Does anyone know what is happening??? Also when it locks how can i get out??? my mouse was fine, but no response from keyboard....dont think there is a way other that reset button....thanks for any help.