I had this same problem with a single 7600 GT on Herd 5. It booted into vesa and when I ran dpkg-reconfigure it told me it couldn't detect what my video card was, I had to manually enter nvidia and ask for higher resolutions.
-- NVIDIA 7600GT detected as vesa not nv https://launchpad.net/bugs/87003 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
