direct rendering scrambles video
 

Debian (started out as Sarge, now upgraded) on an older system with i810 non-upgradeable video card.

If I set up x to use direct rendering, the video for several x-apps is scrambled. Others are not affected and so far all kde apps are OK.

Some of the affected apps are: glxgears, tuxracer ("planet-penguin racer") and Emilia Pinball. Both tuxracer and pinball are so slow as to be useless without dri.

Changing the video resolution does not help, video ram is set at 32768 & screen depth set at 16. dri for this video driver will only work at depth=16.

There doesn't seem to be anything relevant in xorg.log.

I know it is possible to have these apps work with dri as they did work in previous Kanotix-based installations but I cannot figure out what was different about the x-setup with these.

Anyone help?