When I use hdmi out of my Powercolor 4670 AGP, I have problems running games that use full screen. Most just crash..others are forced to use windowed modes as opposed to full screen.
I'm using the official ATI Radeon DVI-HDMI output dongle.
I had to uncheck "Hide modes that this monitor cannot Display" in order to see any selection of resolutions in display manager. I couldn't find a definition that seemed natural in the CCC so I opted to use display manager and seem to have found my TV's native resolution. It seems all resolutions work...perhaps windows or driver "Thinks" these resolutions are not available?? I don't know
Everything works fine with the VGA output...trying to avoid using that as this is my living room PC and trying to avoid running seperate clunky video cable + sound.