There's a regression in the release candidate on i855GM. Ubuntu Hardy had a snapshot of the stable tree up to commit 103dc34f3afc17cea7e086927e124a30c605a686 (despite the package version number). That worked fine. There are two separate bugreports on launchpad:
"After upgrading to 188.8.131.52-2ubuntu2 this morning and restarting X, I noticed that pixmaps had a strange appearance - as though they were being rendered on a 16bit display (which xdpyinfo suggested wasn't the case).
For example, the green gear in glxgears appeared to be composed of alternating light and dark green pixels, instead of a solid area of the same tone.
Installing the previous 2.2.0+git20080107 version brings correct behaviour back."
"After upgrading from 2.2.0+git20080107-1ubuntu2 to current version (184.108.40.206-2ubuntu2), strange artifacts (random red dots, random red lines and red curves made of red dots) started to appear on screen.
Downgrading back to 2.2.0+git20080107-1ubuntu2 fixed this.
Using an i852/855GM notebook (Asus A3L)"
reverting commit a70b59bd44d14e77c9e522dbe225b62a8bcf3050 apparently didn't help.
Created attachment 14217 [details] [review]
diff between the known to be working version and HEAD
The diff looks mixed with multiple commits, could you bisect which commit caused regressions?
How about disable frame buffer compression?
How about current master?
Yep, the latest commit on the stable branch fixed it. Thanks!