Incorrect video with ADC on QuickSilver 2002 GeForce4 MX 2

Question

I've tried to plug my new BenQ FP202W display on ADC port with a LaCie ADC/DVI adapter. The monitor is corretly reconized by the computer, but if the resolution is set to the max resolution (1680 x 1050). The screen goes black and OSD is disabled. However, the monitor displays correctly on 832x624. Some resolution shows intermitent picture.
Thanks you If you can help me to solve this problem.

Answer 1

Since BenQ didn't provide me what should be EDID information, I can't say whether what I have is correct or not.
However, I tried to put the VGA settings into DVI settings, and this didn't work. I tried all simplified settings (GTF, CTV, CTV-RB). Everything failed.
However, the polarity is always reversed, despite my settings, when active it is always horizontal positive, and vertical negative. Whatever is set in Custom Settings.
The DVI EDID dump gives me for the native resolution :
Descriptor #0 is Timing definition:
Mode = 1680 x 1050 @ 60Hz
H. Active...............1680 pixels
H. Blanking.............160 pixels
V. Active...............1050 lines
V. Blanking.............30 lines
HSync Offset............48 pixels
HSync Pulse Width.......32 pixels
VSync Offset............3 lines
VSync Pulse Width.......6 lines
Pixel Clock.............119.00MHz
Horizontal freq.........64.67kHz
Vertical freq...........59.88Hz
H Image Size............433mm
V Image Size............271mm
H Border................0 pixels
V Border................0 lines
Non-Interlaced
Sync: Digital separate with
* Positive vertical polarity
* Negative horizontal polarity
My parameters :
Bandwith : 119 MHz
Horizontal active : 1680 pixels
Horizontal before : 48 pixels
Horizontal Sync : 32 pixels
Horizontal after : 80 pixels
Horizontal freq. : 64,674 kHz
Vertical active : 1050 lines
Vert. before : 3 lines
Vert. Sync : 6 lines
Vert after : 21 lines
Vert. freq. : 59,883 kHz
Positive sync set to true for vertical but this seems to be ignored by the software.
Thanks for helping !