I have tried and tried to find a solution to this problem but to no avail so I decided to post here. I have seen some similar problems but none are exactly the same as what I am seeing.
* XFX GeForce 7950GX2
* Asus M2N32SLI-Deluxe motherboard, latest BIOS
* Ubuntu Edgy amd64
* NVidia driver 9746 (also tried 9742 with same result)
* Kernel.org 2.6.20 kernel (also tried Ubuntu 2.6.17-11 with same result)
* Beryl 0.1.2-0ubuntu2
What happens is this:
1) User 1 is logged in and Beryl is active.
2) I switch away to User 2 with the Switch User feature (this creates a different X server).
3) User 2 logs in, also uses Beryl this works ok.
4) I switch back to User 1.
5) Now I only see a black screen with the mouse pointer.
At this point I can (from another PC) log in and killall -USR2 beryl-manager, (which switches back to Metacity WM), this will *sometimes* work and at other times it will crash the X server.
If I disable Beryl before switching away, there is no problem when switching back. So something is not getting restored properly.
There is a related bug case on the Beryl bug tracker: http://bugs.beryl-project.org/ticket/928
I would surely appreciate any help. I need Switch Users to convince my wife that Linux is better than Windows...