Fedora :: Display Setup With F12 And Shuttle SN41G2V2

I've had display problems with Fedora 12. My monitor could display 1600*1200 in Fedora 7, but I'm having a struggle with F12. I can get 1600x1200 using the nouveau driver but after lots of experimentation, I'm left with:

1. The top line of pixels seems to be repeated 8 - 10 times, shifting the display content downwards so that the bottom few lines of the display content disappear. The mouse cursor can reach the whole of the display but "points to" and "clicks on" part of the display content which appears a few pixels below it.

2. A few pixels of the display content are cropped from the left hand edge of the screen.

Things I've tried:

1. Tried **many** different modelines in xorg.conf and , this is the one I'm using at the moment: ModeLine "1600x1200@50" 162.0 1600 1616 1736 2160 1200 1201 1206 1248 +hsync +vsync I don't know whether all the parameters match up, the monitor flickers a bit at logon so I guess they don't (e.g. the monitor display reckons it's on a 60Hz refresh). At least the display is basically usable though.

2. Tried nouveau, nvidia, nv and vesa drivers - nouveau is the only one which gives 1600x1200.

3. Tried xvidtune, but it complains "Unable to query monitor info" and exits.

System Hardware:
System: Shuttle SN41G2V2/ Athlon XP 3000/ 1GB - "VGA compatible controller: nVidia Corporation NV18 [GeForce4 MX - nForce GPU] (rev a3)" Monitor: Dell 2007FP (1600x1200 native resolution) connected via standard VGA connection - has previously worked at 1600x1200 using Fedora 7

System Software Fedora 12 (2.6.32.11-99.fc12.i686.PAE); installed where F7 used to be (and Mandrake before that!), but /home lives on a separate partition and has not been changed.