848x480 - Intel 815 graphics controller - fullscreen

[myrtille]

I am using the Intel motherboard D815EFV which has the 815E Graphic
Controller.
I have a NEC PlasmaSync 42PD1 connected digitally using a Molex DVI
card/connector. Windows 2000 is the Operating System.

I am using the Intel driver P 6.2 which is the only one that supports
848x480 when you are connected digitally to the monitor.
I now can select 848x480 among the supported resolution but here is
the problem:

I have a tiny desktop in the middle of the monitor and I can't fill up
the screen.

The signal sent for the horizontal sync is 48.3 Hz when it should be
31. The vertical sync is reading 60 Hz.

The sync polarity is seen as negative when it should be positive.

The signal sent by the controller seems to be 1024 x 768

My question is this

1-How can I modify these 2 elements to be able to run that 848x480
resolution fullscreen ?

Thanks in advance for your help

Marjorie