It was my driver version. I spent a few hours wrestling with them the other night, I'm on 11.2 drivers now with SDK 2.1. I noticed that even though it no longer crashes when I stop mining, one of my two GPUs never quite reaches 100%. Granted, I have crossfire enabled, but I'm pretty sure that (once I have time) upgrading to 11.3 drivers will fix the performance deficit in my second card. Independently they both run full speed.
Also, regarding Ubuntu, I spent quite a long time last night trying to get it all set up. I'm pretty sure everything is almost set up...I was following this guide http://bitcointalk.org/index.php?topic=3359.0
to set it up, as I've never touched Linux in my life. I just need to overclock my GPUs in Ubuntu (somehow) and make a dummy plug for my second card and I should be good to go.
Ubuntu is kinda scary though, haha. It seems nice and stable, but I have absolutely no idea how to fix anything myself if I mess something up....I was literally just following instructions word for word with only a little bit of comprehension of what I was doing. I can't wait to see how much faster it is mining in Ubuntu though =D