I just downloaded the Knoppix 5.0.1 DVD, but I have had no luck in accessing the GUI. Everything seems fine during the initial booting sequence, but shortly after configuring peripherals the screen just goes blank and nothing works. Keyboard lights don't respond, the CPU light isn't busy, and the only way to get out of it is a hard boot.

When booting with "knoppix 4", I am able to access the console. However, once I try loading the GUI with startx, the screen goes black.

I am using an ATI X850 Pro on a Dell FP2001 monitor. I have tried a few other Linux distros (SuSE 10.1, Auditor Live CD, and Backtrack Live CD) which did not exhibit any display problems.