THATS WHAT I WAS THINKING...EVEN IF DXDIAG SAYS THERE ISN'T A PROBLEM, THERE MAY BE ONE KEY FILE CORRUPTED. RE-INSTAL DX9C, THEN TRY ROLLING BACK TO CAT. 4.12, OR CAT 5.3. THEY BOTH WORK VERY WELL ON MINE(9600XT, DIFFERENT CHIP THAN X800 BUT THEY BOTH WORK VERY WELL ON MY FRIENDS X800XT) AND DON'T INSTALL THE CONTROL CENTER, AT LEAST UNTIL YOU FIGURE OUT WHAT'S MESSIN WITH YOU