I'm running 6950,,,and I've had REALLY bad results using catalyst profiles W/ far Cry 3. My best performance was using in game setting's only, Since A/A, or Anistropic was glitched. I dunno if still is, but CAP caused serious issues with both my 6950 , and 7970.
I'd try 12.10 if I were You. It has worked WAY better for me with My 6950
Definitely DON'T use that CAP with 12.11,,,,It was Awful.(For Me atleast) 10% drop in performance.I think it's a case of AMD taking forever W/ their Driver's , as usual.Also , when your using The CAP, it is over-riding the setting's/some setting's from the in-game option's menu.(if you have it set to in CAP)
If your running Win7 64Bit, I'd use This driver, With No CAP, and see if it works better.
Just keep in mind that the A/A isn't quite right in game, so try not to get hung up on wanting to use it.
As you can see, I disabled most of the video setting's, and there's Really no Bid difference, except for the lack of glitching from when they are on.
Best of luck, I hope it all work's out for you.And Happy Gaming.
http://www2.ati.com/drivers/12-10_vista_win7_win8_64_dd_ccc_whql_net4.exe
these are my settings , which yield around 60-70 FPS.I hope this helps you out.