SV : here's the thing. I use Cedega lot for CoH... and I couldn't tell a bloody difference between the 8.40 driver and the 8.43 driver. My OGL screen-saver also worked properly. So... as far as I could tell, everything "seemed" to be working after the driver install. The Fglrx control center indicated that the fglrx driver was installed and working properly, with no Mesa malarkey.
So... I'm a little embarrassed to only now go "hey, somebody's right, something is screwy here"
Edit: okay, next troubleshooting step I've taken is to remove the SMP kernel module. Fglrx control center now shows that the system is running under Mesa3D. Cedega now reports I have 3D acceleration... but OpenGL acceleration fails.
edit : next update: used synaptic to reload the smp kernel module. Rebooted, checked Fglrx control Center. It showed that the fglrx driver was loaded. Checked Cedega. Again, OpenGL works, 3d acceleration reported broken.
Used Mepis X-Assistant to force vesa driver. Rebooted, got text login. went through dpkg-reconfigure xserver-xorg forcing vesa as driver. Loaded into X, checked Fglrx Control Center. It will not start as the fglrx driver is not present. Deleted /etc/ATi
Okay, on the reboot, used Mepis X Assistant to install the fglrx driver. No issues reported. Rebooted again.
Checked fglrx control center, and it states the fglrx driver is not loaded. Check Synaptic, and the fglrx driver and kernel module are present. Use Mepis X Assistant again and reboot.
Fglrx control center reports the driver still has not been loaded. Force with dpkg-reconfigure xserver-xorg. Reboot and Fglrx control center says the Fglrx driver is loaded. Check Cedega... still no 3D acceleration.
Okay... I'm honestly not sure what's errored, but something in the Mepis Setup works. I know the driver itself works because I've got it running on another distribution on the same hardware. Part of me wondered if it was related to the older 8.40 profile, but removing the /etc/ATi entry should have cleared that as a potential problem.
So... if you have an ATi card... sit tight.