Ubuntu 10.04, screen is black after locking screen

[Hybrid_theory]

Today my ubuntu 10 workstation has been acting strange. First when locking the screen, i come back and hit my usual spacebar to activate the login window, the mouse just flickers on and off. I have to restart gdm at this point. What then happened was the dual monitor setup got off. I opened the nvidia control panel and set it to the one where each monitor is seperate (forget the name). I didnt like that, so set to twin view which could never properly work. The monitors were getting odd display signals, and the refresh rate was bad. So i removed the nvidia driver and went back to using preferences > monitors. So the monitor setup is fine now, just the locking issue still occurs. The video card is an nvidia quattro of some sort.

I later noticed that there were two screensaver applets. I removed screensaverx, then i couldnt lock at all. After that i reinstalled gdm and ubuntu-desktop. I can lock again, but the same problem occurs with the black screen and mouse flicker. I have to restart gdm to login.

[Easy Rhino]

that is strange. could be a driver issue, but if it just started happening then it could be anything. do you have compiz running?

[Hybrid_theory]

Nah no compiz. One other problem, i doubt its related but hey never know: the psu is nearing death i think. It occasionally puts my comp to sleep on its own, and when ever i shutdown the computer and then hit the power button to turn it on, there's a delayed start; 30 seconds or so.

[Easy Rhino]

Originally Posted by Hybrid_theory

Nah no compiz. One other problem, i doubt its related but hey never know: the psu is nearing death i think. It occasionally puts my comp to sleep on its own, and when ever i shutdown the computer and then hit the power button to turn it on, there's a delayed start; 30 seconds or so.

hrm. could be. doesnt sound like a problem with the OS.

[Hybrid_theory]

Well ive tried swapping some spare video cards that are around. One was an ATI from a mac desktop. And apparently their bootroms from back in the day were set to only work with macs; that you cant see the usual BIOS boot info. I tried that, and couldnt get the OS to show. I tried an ati x550 that was around as well. One of my monitors had half the screen black, and the half that wasnt black was fuzzy. I thought maybe it was the vga - dvi converter i had on the dvi port. So i swapped that and then the monitor said no video signal. So i just threw my fx330 back in so i could get some work done.

Now they found me an 8800gt which ill try out tomorrow. But even if the monitor stuff gets fixed, im thinkin the locking issue will still be there.

I did swap to another machine as well, where the psu is in better shape. No more delayed power ups.