Major problem with the new GE Force 9800 GX2

[Golden_Eagle_FM]

I just installed the new Nvidia GE Force 9800 GX2 graphic board from ASUS with the latest drivers 174.74.
I tested the board and it has a stellar performance.

When playing with IL2 however I got a weird effect. The shadows of the smoke columns on the ground, or of the islands or mountains in the water or in the rivers, or of the ship shadows on the water they all blink (in synchronism) and this is really annoying.
Framerate is excellent and all the rest is perfect.

I use the perfect mode with the latest 4.09 Beta DLL from march 2008.
Landgeom is set to 3, water = 3, effects=1.

I tried many changes of the conf.ini parameters but could not change this fact.

If I put water=0 there are no more reflections on the water, or shadows on the water so there is no blinking any more on water. But still the shadows of the smoke columns on the ground continue to blink.

The blinking frequency is maybe around 5 to 10 Hz so very annoying.
Before I had an Nvidia 8800 Ultra board and had no problem at all with exactly the same system. I just changed the board.

The system is:
CPU is Intel Quad Core extreme QX9650 running at 3.15 GHz
Mainboard Asus Commando
FSB 1333
Memory 4GB Patriot 9600.
Windows Vista Ultimate

Any ideas

Gold