screen resolution to low

Hi,

I have a new installation of w2k on an elitegroup Systemboard with SIS740 chipset (onboard vga).
Installed all the newest W2K sec.patches and ServiceRelease 2. Have the newest drivers installed from SIS.

The SIS640 has a max screen resolution of over 2000x1600 pix.
The maximum i can adjust is 1280x1024.
The monitor is a Miro which dos at max 1600x1200 and it is on 60hz. (so monitor is not the problem)

The BIOS is set for giving the vga a interrupt and its set to AGP and usuageof 64MB of the systemram (total 512MB)

In windows, the driver does NOT have a interrupt to it (no idea why not )

Any ideas how I can get the driver to recognis higher resolutions ?

regards
peter