I am working with Fedora Core 3 and a nVIDIA Fx5200 Video Card.
[gastonv@pandora1 ~]$ /sbin/lspci| grep VGA
01:00.0 VGA compatible controller: nVidia Corporation NV34 [GeForce FX
5200] (rev a1)

I have tried with this in my Screen Section :
[gastonv@pandora1 ~]$ cat /etc/X11/xorg.conf
Section "Screen"
Identifier "Screen0"
Device "Videocard0"
Monitor "Monitor0"
DefaultDepth 24
SubSection "Display"
Viewport 0 0
Depth 24
Modes "1024x768" "800x600" "640x480"
Option "TwinView" "true"
Option "TwinViewOrientation" "Clone"
Option "TVOutFormat" "SVIDEO"
Option "TVStandard" "PAL-B"
Option "SecondMonitorHorizSync" "30-50"
Option "SecondMonitorVertRefresh" "60"
Option "MetaModes" "1024x768,1024x768;800x600,800x600;640x480,640x480;

Booting up My Computer shows very good and correct the colored
GRUB-Screen and The Linux Login Text Procedure.
After that I see different colored screens, red, blue and green and at
the end a black screen with red lines.
Opening an application gives a blinking colored block ...
Logging out gives at the end again a correct logout text.
Please anyone help me?
Many thanks in advance,
Gaston Verhulst - Belgium.