I bought a new PC and its configuration is this: ASUS P5K SE INTEL P35 1333MHz FSB SOKET 775 ANAKART Intel CPU E8400 3.0 GHz 1333MHz 6MB Core2Duo POV NVIDIA 8800GT EXO OVERCLOCK 512MB 256BIT DDR3 (DirectX 10) PCI-E x16 GPU (R-VGA150858EXO) OCZ NVIDIA SLI 2 GB 1066 MHz CL5 DDR2 Kit (2x1GB) - OCZ2N1066SR2GK SAMSUNG 320GB 7200RPM 16MB CAHCE SATA2 Hard Disk SAMSUNG SH-S203B 20X SATA DVD Writer LG L1960SR-BF 19" 2ms LCD MONITOR (Artistic Series) GIGABYTE GZ-X5 460W BLACK CHASIS I installed XP and Ubuntu and everything was OK. I could play Doom3, PES6, No One Lives Forever and Max Payne flawlessly, using the best graphic settings. But when i'm listening to music with Windows Media Player, the screen goes pink and all i see is cursor. But cursor changes depending on its location. It's shape gets different when it's on text, for example. The Media Player runs still, i can hear the music. And all programs (like IMs) work as they used to be. I use alt+f4 to restart my PC. The same thing happens everytime i run Media Player. I dediced to use Winamp then, and everything was OK. But then some games weren't running good anymore. For example, Painkiller. I run it, the game begins, i kill some monsters and suddenly the screen goes black and then i see "Power Saving Mode". The music kept for a few seconds and then stop, and keys do nothing. Monitor's led turns blue to orange. Just like when the PC's turned off. Reset was the way to go. I tried it again and everytime i try to play Painkiller, same thing happens. Then i tried Vampire the Masquerade: Bloodlines. In some spesific locations, same thing happens except that the music doesn't go on. Instead, it plays the last 10ms of the sounds, crappy noise. I thought it was bug, but it can't be. Because i played the game in another PC and nothing like that happened, these locations worked fine, as if there is no bug. My friends said that it might be of heat. But when i turn on my PC and play Painkiller, i have the same problem. I have no problem playing Doom 3 for 10 hours at Ultra Settings and 16xAA though. Some others say that it's about GPU. I installed the latest drivers from nVidia's site, same things happen. But i still think that GPU is the problem.