It usually to be 1200Mhz all the time, until the time it dropped to 400Mhz, this problem starts happening.
I turned on Aero scheme on Windows Vista Ultimate.
Is the graphic card fault or software fault?
If the graphic driver, what can I make it better?
The issue is like red coloured pixel over patches of desktop, and then turned on blank screen.
Any further actions, you see any tearing and abnormal graphic even I not using game, or on desktop.
This issue happen a while after boot up or leaving the computer for long time.
It happen on dual DVI monitor, i do not have problem with HDMI HDTV.