Hey Migelloh - welcome to the PCHF!
I would say your problem is WoW...and I'll stand by that until the day I die....however...since that isn't the real answer, lets try and figure it out for you...
From the sound of your problem, it's either a windows problem, or a driver problem. First upgrade your chipset and video card drivers. If that doesn't work, goto Start -> Run -> sfc /scannow
If that doesn't work, follow the Prework steps located in PJ's signiture.
Hope this helps!
