Hi! I'm not here with a query, but rather a solution. Using Knoppix 3.7, I found that from the CD boot I was able to run the provided games (eg. Chromium) smoothly, but when I installed it on the HD they were so slow as to be impossible to play. A quick check with glxinfo showed the DRI was not present. My video card is an ATI radeon 9000 mobility. I spent a whole day on this, and finally came up with the solution, which is a two-parter. Firstly, you must install the kernel driver radeon in order to enable DRI ( I noticed this was present in the CD boot but not the HD install). Secondly, you must edit XF86Config-4 and set the option "ForcePCIMode" for the video card. Yes, you will no longer get AGP enhancements, but this is hardly noticable in the desktop environment and DRI has a much greater impact on the performance of games.

:P