I have a Sapphire Radeon HD 7950, and today I decided to use the Overdrive function in the Catalyst Control Center. I brought my gpu clock up to 1150mhz from the default 950mhz, and my memory clock to 1500mhz from the default 1250mhz. After that I started to play some games to see the performance difference. I was playing Crysis 2 for about a minute until my screen turned black, but i could still hear the game running, I tried doing ctrl alt delete but nothing happened, it just stayed black and the game sounds stayed. So i restarted my computer, and i figured it was just the game or something, since i did torrent Crysis 2, So then I instead tried to play my Legit copy of Far Cry 3. The samething happened except instead of a black screen, it was a pale yellow with beige stripes and i could still here the game sounds. This only happened after i used the Over drive function.