If you want Ultra Mode on Linux, it looks like your best bet is an ATI graphics card and Wine. Using the 9.11 drivers, Wine 1.1.43, and an ATI 4350, all Ultra Mode features work, at about the framerates you'd expect from that card.
NVidia doesn't work: none of the Ultra Mode features are available, and very few of the regular mode features are.
If you want Ultra Mode on Linux, it looks like your best bet is an ATI graphics card and Wine. Using the 9.11 drivers, Wine 1.1.43, and an ATI 4350, all Ultra Mode features work, at about the framerates you'd expect from that card.
NVidia doesn't work: none of the Ultra Mode features are available, and very few of the regular mode features are.