Sometimes (very rarely actually) I have a problem that when I try to shut down my desktop, it will freeze with the following screen and I can only shut it down by pressing the power button for 8 seconds:Does anyone know why this error occurs (I am guessing it is because of the proprietary fglrx-driver) - or how I could get more diagnosing information if it reoccurs? I guess there would be a lot more information than I can capture with a simply photo, but as soon as the screen appears it is impossible to do anything.The problem is, it occurs very rarely (maybe once a month) so it is not really a big hassle and I can not willingly recreate it.I would just like to know what exactly is causing it.Edit: After stumbeling over this bug - this seems to be the reason for it: the fglrx driver seems to the buggy.
Linux Mint does not shut down
shutdown;kernel panic;failure
Such rarely occurring crashes are very hard to debug. It can be a hardware problem, driver (flgrx, as you've noticed) issue or even a kernel bug. The easiest thing to do in your case is to change the video driver - of course that will only prevent further crashes only in case the driver was the problem source. Unfortunatelly, the right direction to go is not obvious: sometimes upgrading the driver can help, sometimes it can be better to rollback to a previous stable version. You will have the highest chance of ruling out driver bug cause by switching to the open source alternative driver for ATI cards: either radeon or radeonhd.Otherwise, if you really want to dig into the root of the problem and potentially help kernel/driver developers, you'll need some kernel debugging instrumentation. Have a look at LKCD, described in this article.