I was playing Vice City the other day and in the middle of the game my video froze and then went to gray lines. I thought it might be a heat issue, so I turned off the computer, let it cool down and restarted. I then could view the desktop, but as soon as I started any game requiring 3D (Vice City, UT 2003), the screen ended up displaying weird artifacts. The same thing happens when the computer is cool. Am I hosed?