R9 270X - poor 3D performance with Catalyst, resolution trouble with radeon

Question

I recently bought an XFX Radeon R9 270X and run Ubuntu 14.04 on it.

I use it via HDMI to a (plasma) TV. I also make use of HDMI audio through it. Before my upgrade, I forced xrandr to use a custom resolution with my Intel integrated graphics via VGA. When I booted into radeon (open source driver), it was immediately obvious that it was too large for the TV. I later found out this might be because of 'overscan' -- a feature which I cannot turn off through any menus on the set.

The resolutions listed by xrandr were all inappropriately small. My TV does not allow me to calibrate the position of the display (IF the source is HDMI, it does via VGA however), and they were either too small or, as aforementioned, too big. As I understand it, the EDID for my TV has always been incorrect, and this is not a new issue. However, with both radeon and Catalyst, I am unable to force the custom resolution that I used to.

I decided to try Catalyst because it is a newer card and its 2D/3D performance is supposedly better. The default resolution is much better, and fits most of my TV. If the calibration worked, I could probably make it fit perfectly. The only issue here is a small black border; this is something I can live with. Wine performance was poor (as described again later).

I tried to uninstall Catalyst at this time and go back to radeon, but this led to Xorg crashes. I had to remove all of Xorg and start again to get a new chance at radeon. Recovery kernel boots allowed me to turn on SSH, but the crash log would not be on disk because I had to hard power-off the system as it was 100% non-responsive. At this time, I ran "Xorg -configure" as a crap shoot. I saw a stack trace and seg fault, but I am unsure if this would be helpful, nor do I know if it was the same crash that was causing the black screen. Again, I was able to circumvent the black screen/crash issues by completely purging my system of all Xorg packages and installing the xserver-xorg-video-ati package along with others to bring back radeon.

My attempts to fix the resolution by adding the mode to /etc/default/grub were futile, and so I went back to Catalyst. The process of reverting to radeon was extremely painful and a lengthy process. I was unable to successfully grab any crash logs at the time, it would boot into a black screen. SSHd, despite being installed, wouldn't 'come up'.

At this point, after getting tired of the performance, I installed xorg-edgers and the latest wine1.7. It seemingly had no positive effect.

In Wine (again, with Catalyst), I am unable to even watch Skyrim/Fallout 3's video introductions, let alone the game. My Skyrim save from the 'integrated days' allows me to quickly jump into the game, but it's still unsatisfactorily slow. Fallout 3's introductory video stuttered and was unwatchable. I certainly appreciate that Wine may not be perfect for gameplay, but it was far superior via Intel, which doesn't make sense. I was expecting improvements everywhere with a new graphics card, not regressions.

Native Linux games on Steam performed better than Wine games. Valve games were hit-and-miss: TF2 was acceptable, L4D2 wasn't. Both were with and without video tweaks respectively, still OK and below average. Goat Simulator (ran in Linux) looked like this. I peeked at the video settings and changed the view distance to be better, as I could see barely anything around the player, but this had no effect even after a game restart.

Could somebody please help me with my Catalyst performance/rendering issues or radeon's resolution hell? Any tips, hints, or support would be extremely appreciated.

TL;DR:

• Poor 3D Catalyst performance.
• Unsatisfactory rendering of goats.
• Can't set correct resolution with radeon, when Catalyst gets pretty damn close by default.
• I can live with Catalyst's resolution if it'd just run games well.