I also encountered the black screen. The DVD installer finished fine, but after a reboot I see the kubuntu bar and can watch the start-up console messages, but shortly after the tones the screen goes black. However, pressing 1-5 does nothing for me. Also, when the system has booted and I get the black screen, caps lock doesn't seem to do anything; I don't know if this is normal or not. Hitting power seems to shut down the system properly, but I can't get any video to save my life.
Hardware is a Dell Dimension 2100 with a GeForce FX5200 and some old model SoundBlaster sound card and 3Com 905B ethernet. I realize it's pretty old, but I just want something basic to watch AVIs and DivX with. It used to run Windows XP okay, but I hoped this would work better, and I really don't want to go back to MS.
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It seems that MCE Linux is not dealing with the video cards correctly. The BIOS has an option to use on-board or add-on video as the primary. There is no option to turn the on-board video off, nor is there a jumper on the motherboard. As long as I have an add-on card, MCE fails to use either card properly, regardless of the BIOS setting. If I physically remove the GeForce card, MCE linux tries to use the on-board video, which is limited to say the least, but X starts and there's some progress. Any hints on how I could get it to use the GeForce and ignore the on-board video?