I'm using Catalyst 8.12 on a Thinkpad T60, Linux 184.108.40.206.
I've been running Xorg 7.2 and everything has been playing
nicely. Today I updated to Xorg 7.4 and reinstalled Catalyst,
and now I'm seeing a few nasties, viz.,
* Artifacts in the form of narrow vertical black lines in
e.g. xterm and Nedit. These go away if I force a redraw
(shade and unshade the window).
* Crappy GL performance. For example with glxgears (and
also the GL xscreensaver modules). I get a high frame rate
OK, but it's like there are diagonal black bands passing
through the image.
Any ideas on whether this sort of thing can be fixed by
tweaking xorg.conf? My fglrx entry is pretty much vanilla.
Sorry, I'm not finding the exact option you mention. Is this the
same as aticonfig --sync-vsync=on? I turned that on and restarted
the X server but it doesn't seem to make any difference. Possibly
relevant: I notice that the frame rate reported by glxgears under
Xorg 7.4 / ATi x740 is almost twice that reported with Xorg 7.2 /
ATi x710 (i.e. 7000+ vs. about 4000).
Ah, OK. In amdcccle there's a config slider labeled
"Wait for vertical refresh" with a scale "Performance <->
Quality". Out of the box the slider was at the Performance
end, but I've moved it to Quality, which corresponds to
Option "Capabilities" "0x00000800"
in xorg.conf. I'm afraid this doesn't make a visible
difference to the GL performance.