Why does my computer run dx11 bad?

845ToastT

Honorable
Dec 24, 2012
6
0
10,510
When I go to play Far Cry 3 on dx11, it will only run at 15-20fps and lag every couple of seconds, but when I run it on dx9, it will run great at 50-65fps. Also, it doesn't seem to want to run Medal of Honor Warfighter either. It'll say that it's running it at 90-130fps, but it will lag and freeze every couple of seconds. Even on the lowest graphics, it will still freeze every couple of seconds (90-130fps was on ultra and high settings). It's really annoying and almost unplayable. I just finished sweeping all of the amd drivers off my computer and re-installing the latest and greatest. I also made sure the latest directx was installed. Anybody have an idea why it does this? I would think my computer is capable of running it.

My rig:
-AMD 6950 2gb x2 (crossfire)
-Intel core i7 950 3.07ghz
-6gb ram
-Sabertooth x58 motherboard
 
Both of my graphics cards are in x16 slots. Windows is fully updated. I couldn't find any bios updates or firmware updates for my hard-drive. My computer is clean of viruses. I do have a question, the bridge between my graphics cards has two spots it can plug into on each card. Could which slot it's plugged into effect it? Do I need 2 bridges to fill each slot?
 
Oh, ok. I will try different games. I have Operation Flashpoint and Borderlands 2 to install aswell. But I'm still wondering why Far Cry 3 runs better with crossfire disabled and set on directx 9 from the options menu.
 
Far cry 3 has some issues with crossfire and directx 11 for amd cards. I run 3 7970s and still dip down into the mid 50s in some points of the game. AMD did release a CAP on 3 Dec to help fix some of the issues...not perfect but a bit better.