Dear Mike, We recently tested fedora on a dual Athlon machine with an ATI Radeon 9600 with two outputs, VGA and DVI. Chipsets 4150 and 4170 combined on the one board.
I tested this every way I could think of, modifying the XF86Config for one or two screens, etc. But no joy. I'll get more details after the weekend. VESA was fairly stable. Regards, TC