Ubuntu: Dead Duck

How enthusiastic I was about Ubuntu in my last post :-)

Ubuntu gradually white-screened more and more on reboot, shutting down and starting up ……
Now I cannot even boot off the installer CDs !!

I tried resetting the PRAM.
I tried what is suggests in yaboot.

I have a non-standard video card in the Cube, but it obviously works and I can’t see Ubuntu caring what was originally in a machine as old and obscure as this.

I am disappointed now :_(