I cracked the case last night and pulled the sticks out and checked to make sure there was nothing in the sockets. They appear clear. I also tried a couple of variations on the order the memory went back in and nothing seemed to make any difference. At least until this morning. My machine gave me a BSOD for some reason. That hasnt happened the entire time I've had this machine and I'm pretty abusive toward it in terms of running a lot of stuff on it all at once.
I think I'm just going to go buy a pair of 2Gb sticks and see if they fix this problem. If they don't I'll find a replacement motherboard.