I had overclocked my 6870 ATI to a high level after reading some tests. After awhile as for any overclocking it became unstable so I reverted it back to defaults. Now, Every say 10minutes while playing a game I'll get low FPS, Such as 1 - 2 FPS for about a minute and then it will start working again. Am not sure this is due to me overclocking it and have caused damage to the graphics card or maybe a ram issue.