When you have a DVI connection in digital mode on an SMP machine, you have problems (i.e. doesn't work at all, machine hangs).
It is in analog mode.... However that being said, with 4191 (when DVI worked) the same behaviour manifested with either the DVI output or the HD15 output.
I've tried turning off UBB, alas that did nothing.
I'll try it in non-SMP mode now.