I have noticed some odd behaviour on a Dell 4550 when doing a knoppix shutdown, it would turn the PC off after asking you to remove the CD. Upon pressing the power on at this point, the PC would turn on but the display would not, not even the BIOS boot screen, monitor would stay in standby. Then if I would actually unplug the power from the back of the unit and plug it back in, it would boot up normally. I evenually figured out a way around it (issuing an init 6 instead of doing a shutdown). I'm not sure if the 2003-03-26 version has this problem, I think I did shut down once the regular way IIRC and it did not exhibit the lock-up.