I just installed Catalyst 9.5 and was thrilled to see a bunch of HDTV settings available - the option to add a 1080p60 mode, for example, and a slider to adjust the card's default scaling - which, along with the super user mode shortcut solved the problems I was having with catalyst 9.4.

So I changed my settings and enabled "desktop effects" and then went back into CCCLE to see if I'd missed anything, only to find that the HDTV settings were now gone. I restarted, thinking I'd missed something, and now my system won't boot. I can't even hit CTRL-ALT-F2 at what should be the login screen to get to a text terminal and rerun the setup app or whatever.

Any ideas what would cause this?

Ubuntu 9.04 64-bit, kernel 2.6.28-12, Radeon 4850, Toshiba 32RV530U TV.