Fei_Hung

You did not read my post carefully as it seems.
I am not asking you to distrust anyone.
Just do this for me and test your MEMORY cards not your video card at all.

In the old days, there was a virus that could overdrive your CRT and burn the HT transformer we call the Flyback.
The cards during such an assault never get harmed. That problem was due to upgrading cards without upgrading monitors.

Unless you have short-circuited your video card by dropping a conductor on it while power is on, there is no reason for it to go out of order.

Now try to do as I told you with your memory cards.
Memory cards.
Not your video memory.
The mother board memory, there is nothing to lose here, so try it out please.