same/similar problem - I cannot get any feedback from the system to give any details. I have an ATI 9660 on Asus A8V-MX with AMD64.
I have been able to install i386 Ubuntu with some problems, but AMD64 install gives a blank screen and no output/action from CTRL- ALT-F1/F2/F3/F4/F5/F6/F7/F8/F9. -- [regression][rv280] black screen and console freeze when X starts - drm lockup https://launchpad.net/bugs/67487 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs