[hblug] bois flash killed my gdm

[racepics at paradise.net.nz]

Yep you read it right - impossible as it would seem, upgrading my bios ( to
accomodate a quad-core ) has killed my GDM..

How? I dont know!

BIOS is all ok now - four cores recognised. But booting ubuntu produces 
Fatal Server Error: no screens found etc etc 

So.... Can someone explain to me how to get GDM fixed or reinstalled.

Or perhaps some command line expert would like to do mea favour? 
( coffee, beer, hardware, money, bribery - all things possible )

help!

chris