for me personally, I found that any loading screen in GRID runs like total crap with an AA settings greater than 2X. It quadruples all load times for me if using more than 2x. So you can either drop to 2x or below, or you just have to sit through them. I've been running at 5760x1200 with 2X with no problems with crossfired 5850s. Once you actually get to the race, it will run fine with 4 and 8x AA, its just waiting the two minutes for each round to load. Hope this helps. Also, I'm using the beta 10.3
thanks for the advice. that was exactly the problem. when setting eyefinity resolutions, the game automatically set AA to 2X for some reason, even when I set it to none. I had to modify the XML file but once I did, the game loaded up fine.
I also had to modify the preset file so the game would recognize my G27 wheel. But now everything is groovy. thanks again