Why am I getting worse performance with the ATI Radeon HD 5570 than other people report?

Question

I bought a computer a little while ago that has two ATI Radeon HD 5570's in it.

First, my computer's specs:

Motherboard: Gigabyte GA-880GA-UD3H
AMD Phenom II X6 1055T 2.8GHz
8GB DDR3 1.333 Ghz RAM
1TB 7200 RPM HDD
Dual Radeon HD 5570 1GB VRAM
Windows 7 Home Premium 64-bit

As soon as I got the computer I installed the newest drivers for the graphics cards, and set them up with AMD Crossfire X to work together.

The first game I played on the computer was the Tera Beta. People running worse cards than mine were getting higher fps. I had to lower the settings to get over 20 fps.

Then I played Skyrim and it ran like crap. With Anti-Aliasing on, I get like 10 fps, with it off I can get 30, but it still feels like I get 10, the controls seems clunky and unresponsive and I've played Skyrim, it's not like that.

I played around a lot with changing settings and disabling AMD Crossfire X (some games run better without it, namely Skyrim) I overclocked the GPU and VRAM clock speed and that helped some more.

On Batman: Arkham City I get between 25 and 30 fps, but the controls feels smooth and I the frames don't seem to move slow.

However, on Skyrim I get bwteen 45 and 60 fps but the controls still feel weird and when you rotate your character you can easily see every different frame.

Don't even bother with The Witcher 2 and these cards, I still get 9 fps at the most on that game.

Is there a problem between some games and the 5570? Is there a setting that needs to be changed? This problem has been plaguing me for the last few days and I need some assistance. Maybe someone else has had the same problem.

Note: I know some people using the same card as me who can play Skyrim just fine. There are Youtube videos of people using 5570's and playing Skyrim smoothly, so it must be some setting I have wrong.

I have tried both cards alone in each port and see no difference in performance at all.