5870 White dots and flickering in dx9

Hi!

I have a Sapphire 5870 and has been enjoying it for the last two weeks.
I have played Men of War without any problems and World in Conflict both runs great.

A few days ago I installed Operation Flashpoint: Dragon Rising. When I tried to play it I had a horizontal line on the monitor about 2" wide that was flickering.
I then tried to play COD 4 and there I had white dots flashing all over the screen when I tried to play. This was all done with stock speed on the card and no heat issues detected, I even had the fans running at highest speed just to make sure it wasnt a heat problem.

So I thought that this maybe a driver issue with dx 9. I installed other drivers without success.
Then I tried to run OFR and COD 4 and underclocked the card to 600 Mhz on Core and 900 Mhz on memory and then all the issues were gone.
I have 750w psu and used to run a 9800gx2 and a 8800gtx simultaneously so it should not be a psu issue.

The only thing left for is if it might be a problem with Windows 7 and the drivers but I havent found anyone with the same problem as I.
Any input on what might be causing the problem would be great before I return the card.
Thanks!

Rather than a clean windows installation, try to clean all of the nvidia graphics card drivers from the system using a driver sweeper/cleaner program.

If that doesn't work, then try different ati drivers. Sometimes the newest isnt' always the greatest.

I am suffering from the same thing. I have a sapphire 5850 though...ever since i tested crysis on it...all i get are artifacts like im overclockin the memory or somethin...it has progressed until it does this all the time..playin games or not..I am trying my best to figure this out b4 i send it back..but im trying to wait on my 2 intel drives to come in the mail..no point of reloadin windows twice...if u find a permanent solution share it!

Tried the card on a vista 32 comp but I get the same errors.
Looks like Im sending this card back.