Gainward Ultra 960 GS TV-DVI-DVI (5700 Ultra) is flickering!

Hi,

I have bought a Gainward PowerPack Ultra/960 GS with
nVidia 5700 Ultra Chip on it and 128 DDR2 RAM.

This video card has two DVI connectors.

I installed this card on a MSI K7D mainboard. It is a
SMP board with two Athlon MP processors on it.

In the first 60 minutes, the computer is running, this
card causes a flickering on my TFT panel, which is
connected via DVI cable to this card.

The flickering is like plugging DVI cable off and plugging
it in back after one second. The TFT panel is showing
a error message "signal lost".

I have checked all cables, but with no luck. If I install
my old Matrox P650 DVI, this flickering do not appear.

This flickering happens, when I start Explorer or windows
are painted by the system. Not every time, but about 5
times in one minute.

I have installed the latest drivers.

Somebody any ideas?

Regards,
Thorsten