Install issues with Appian Jeronimo Pro (graph) card

[F Da Costa Gomez]

Hi,

Decided to give Ubuntu another go on a Dell gx110 with an  Appian
Jeronimo Pro (dual monitor)  graphics card. I believe its based on the
Permedia2 'thing'.

The whole installation goes smoothly until the gdm display manager is
started. It goes in and nothing ...
Screen goes blank and that's it. There is a signal on the card but
nothing shows. To make things even worse, i can't switch to console
mode either using ctl-F1.

Any suggestions (maybe someone has encountered this behaviour as well)?

tia,
Fermin DCG