hd 5850 screen flickering

[nugget]

when the card is overclocked, i get screen flickering while in the menu options of a lot of games and some applications. on the desktop everything appears fine. the flickering only occurs when the card is OC not when it is at default.

 

[nugget]

forgot to add that games run fine while playing, only the menu screens do this.

 

[Albuquerque]

Obvious answer: your overclock isn't quite as stable as you think it is.

I've got a 5850 that does 950/1150 clocks without flickering issues. Now, at 1000+ speeds on the core, it starts having lots of problems...