One solution is to download an "antilag" file with a d3d9.dll but this caused some really bad screen tearing. The other, which I was using up until recently, was to run in windowed mode (but as you'd know, disables crossfire). There are a few other solutions that either don't work or have other weird side effects.
The fix that worked for me was capping the FPS to 59, and v-sync still works (so no screen tearing). In the latest beta of http://forums.guru3d.com/showthread.php?t=357421 they added framerate capping (Nvidia recently added this into their drivers I believe... come on AMD!). Just add TESV.exe to the application profile properties, click the setup icon and add 59 into the framerate limit box. I can finally play the game with crossfire, in fullscreen mode and without the mouse skipping/stutter. Message me if you need better instructions.
I had the same issue as
R4di4ti0n.
I just fixed it with Nvidia Inspector, selecting the Skyrim profile and set framelimit to 60, with Vsync enabled in Skyrim ini. No screentearing, no jitters!
No idea why Skyrim's V-Sync doesn't work on it's own, considering it's 60FPS.
Good lord, I spent about 5 days trying to resolve this. THANKS
EDIT: Sorry, forgot you were on AMD, bro. Just use a framelimiter. Here's one:
http://skyrim.nexusmods.com/downloads/file.php?id=34
here's something else, idk
http://skyrim.nexusmods.com/downloads/file.php?id=48
unfortunately, looks like they use a dll hook. Which means you maybe can't use ENB and stuff, if you're into that.
There are probably other AMD tools out there that will do it. Maybe they won't need a hook. Hopefully AMD gets one in their Control panel soon.