On 11/11/2008 17:54:18, Chris G wrote:
... It all installed OK without any problems and ran OK. However since I set the graphics resolution to 1600x1200 (the display's default) it crashes *totally* on exiting from X. It's a total, hard, crash - CTRL/ALT/Fn won't switch to a text console, I can't ssh into the system (which I can before it has crashed) and I can't ping the system.
There is one other symptom, when I try and switch to a text mode console (using CTRL/ALT/Fn) even when the system is running OK I get a message from my monitor saying "this mode isn't supported" which seems a little odd on a monitor capable of 1600x1200 at more than 60Hz.
I would take a guess that either X or one of the kernel drives does not understand all the registers on the graphics card so the card is not being put in a consistent state when X exits or hands the card back to the console/framebuffer driver to switch to the text console. Depending on what happens next the card is left with the wrong settings (i.e. not those for the text console, hence the message) or the kernel is fooled into doing something that results in the crash.
I do not know how you would debug this in the sense of knowing exactly what is happening. There will be some info in the X log file but obviously once the the kernel is dead it doesn't write to disk anymore.
I has a case of something similar when text mode used the framebuffer device and whether or not there was a crash depended on the exact settings of that framebuffer mode, i.e. what resolution, depth and refresh rate. I did not try different settings in X to see if it was just a certain combination that was problematic because I spend most of my time in X and didn't want to compromise on that. Instead I reverted to having the text mode use the old (non framebuffer) console driver and that was reliable. Since then problem seems to have been resolved and framebuffer and X co-exist though I do not know if it was an update to X or the kernel that fixed it.
Good Luck, Steve.