Fedora 8 doesn't see my external monitor

Friday, 29 February 2008

xrandr reports "VGA-0 disconnected", but it certainly is connected, and
both Ubuntu and XP can find it OK on the same hardware.

I suspect a very recent ATI driver update has made this worse: xrandr
used to find the screen, though it was blank.  I could make it mirror
the laptop display by saying
"xrandr --output LVDS --mode 800x600" followed by
"xrandr --output LVDS --mode 1024x768"
But now nothing seems to work...

Laptop attached to docking station, and through that to an external
display.

Booting F8, external display behaves normally at first, but when
graphical stuff starts, it goes blank and stays blank.  Laptop
display continues to work normally.  

I'm only trying to display the same desktop simultaneously on both
displays.  No split desktops or double desktops, or anything fancy.

It all worked properly with FC5, and subsequent upgrades to FC6 and then
F7.  Problem appeared only on upgrade to F8.  All F8 updates applied.
Everything still works normally if I boot Windows XP instead of F8.

Config is: Compaq Evo N1020v laptop with Radeon IGP 340M graphics.
External display is just an old Gateway EV500 15" CRT.  Both displays
are 1024*768.

/etc/X11/xorg.conf reads:
        Section "ServerLayout"
        	Identifier     "single head configuration"
        	Screen      0  "Screen0" 0 0
        	InputDevice    "Keyboard0" "CoreKeyboard"
        EndSection

        Section "InputDevice"
        	Identifier  "Keyboard0"
        	Driver      "kbd"
        	Option	    "XkbModel" "pc105"
        	Option	    "XkbLayout" "gb"
        EndSection

        Section "Monitor"
        	Identifier   "Monitor0"
        	ModelName    "LCD Panel 1024x768"
        	HorizSync    31.5 - 37.9
        	VertRefresh  50.0 - 70.0
        EndSection

        Section "Device"
        	Identifier  "Videocard0"
        	Driver      "radeon"
        EndSection

        Section "Screen"
        	Identifier "Screen0"
        	Device     "Videocard0"
        	Monitor    "Monitor0"
        	DefaultDepth     24
        	SubSection "Display"
        		Viewport   0 0
        		Depth     24
        	EndSubSection
        	SubSection "Display"
        		Viewport   0 0
        		Depth     16
        		Modes    "800x600"
        	EndSubSection
        EndSection

If anyone can see what's wrong here, I'll be very grateful!

Gordon Hay