pb Ti install trouble ( graphic )

[yellowdog-newbie@lists.terrasoftsolutions.com]

Hello, 

I tried to install YDL to my PBTi 667.
The graphic install didn't work ( black screen)
I did the install in text mode, but when I tried
to boot on my new os, black screen again.
The YDL boot, and I supose that I just don't see it.
I try to go to a regular console with all key combination and the key 1 or 
F1
impossible. I try to kill X with ctr-alt-delete , that produce some line in 
the screen and
always the black . 

How change that ?