I was running 2 6850's in xfire which worked flawlessly with skyrim but have recently upgraded to an R9 290 and the game has started glitching ever since. I swapped back in the 6850's and it ran perfectly fine again.

I have the standard version of skyrim with no expansions and have tried doing a clean sweep of the drivers and installed the latest 13.12 driver pack from AMD along with reinstalling the game itself.

Now on to the details of the issue I am seeing. Water textures flicker, it constantly sounds like I'm running through water when I'm on land, and I have had some very strange things occur in dungeons/caves where passageways become impassible as if there is an invisible wall in my way or I'll randomly drop through the floor or a bridge to the ground below. Has anyone else experienced anything like this, if so were you able to find a fix for it?

Your symptoms sound like a driver conflict, is it the same driver that works with your crossfire setup?

Sometimes the latest drivers aren't the best choice so maybe trying an older version may be worth a go.

You could try to disable the A.I feature on your Ati CCC panel.

You could try to use MSI afterburner and set your FPS limit 59fps.

You could play it windowed, and download the Simple Borderless Window mode. http://www.nexusmods.com/skyrim/mods/4/?