Comment 29 for bug 38915

I have recently installed 7.04 Feisty and have narrowed the problem down a bit trying to get my ATI x800-PRO to support two monitors.

editing xorg.conf, disabling Composite causes the bug to occur. I can repeat by doing this:

1. Add the following line to xorg.conf:
Section "Extensions"
        Option "Composite" "0"
EndSection

2. Switch users, log out or hit cnt+alt+backspace = black screen hang

3. Remove the above line from step one 1 repeat - the black screen bug goes away in all cases.

Hope this helps.