Just upgraded to the MSI PCI Xpress motherboard and installed a MSI NVidia 6600 256k pci express video card. Upgraded the RAM, and put in a new memorex 16x DVD recorder and a 200 gig HD. Now I'm having problems. When the system is used for a long period, like gaming, it gets hot, I can smell the overheating...and the video begins to halt...then start up....and halt and so on...expecially in HalfLife2...then finally the system locks up. Not sure what the problem is. Also, in two other games, Delta Force Land Warrior and Diablo II, a white area appeared at the top of the screen, and under that, lines of white that flickered into the image. This was cleared up when I rebooted the system. Further, when I open two or more windows on the desktop, they become blocked and I can't switch windows...the second will be all white or over written with the one on top. System is slow and sluggish. I've reinstalled drivers, ran adware removal software and done virus checks. System is clean. Any other ideas?