Well, I wrote some simple code to read the bios into memory, and point BiosBase there. What I didn't do was test that the nvidia driver even honors BiosBase, and the word is that it doesn't
So, back to square one here for me... I'd really hoped I'd be able to solve it with this (albeit incorrect and hackish) workaround. I really feel like throwing this thing in the bin when I have to boot Winblows XP, and then
*nix every boot if I want decent gfx...