More reading, more misadventure, and definitely more than I can remember, but I got it working. The short version is that
I installed fglrx (ATI proprietary driver), worked with it to get back to a stable desktop, and
followed this guide from the Debian Wiki (sort of).
I learned a lot as I went (I think). Fglrx seems to like to have an /etc/X11/xorg.conf, and I approve of this. It's neat that the open source drivers are autodetected, but I never did find a good guide explaining how to tweak things on an install with no (and I guess no need for) an xorg.conf.
An important note, compiz is up and running happily on my system and the output of compiz-config is as follows . . .
- Code: Select all
Gathering information about your system...
Distribution: Linux Mint
Desktop environment: GNOME
Graphics chip: ATI Technologies Inc RV630 [Radeon HD 2600XT]
Driver in use: fglrx
Rendering method: None
Checking if it's possible to run Compiz on your system... [SKIP]
Checking for hardware/setup problems... [SKIP]
At least one check had to be skipped:
Error: No rendering method in use (AIGLX, Xgl or Nvidia)
If I did it again I'd try 'compiz --replace' as soon as the fglrx install was stable. I'd recommend trying without tinkering with xorg.conf as the above guide suggests first, as the hairiest moments came when I had to boot to recovery mode and comment out my alterations from the command line. I think I did a lot of extra fighting trying to make compiz-check happy when it wasn't necessary.
Everything I read suggests that the open source drivers are perfectly capable of running compiz, I just found a different way in my meanderings. I'm sure I've done it the hard way. I just thought to share what I could remember in case it helps someone later.