I had the exact same problem it turned out that it WAS the power supply ....or at least a dodgy molex connector in my case. every other program on my system ran fine except BF2, I tried everything i could find to determine if it was a hardware or software problem but got no results .....eventually i got a pop up error from my msi 6600gt card saying that it wasnt getting sufficient power and that it was winding all settings back down which may make my system unstable......mind you this was after 36 hours of non stop testing and benchmarking programs to try and replicate the error....all i did was disconnect the connector from the card pulled the card out (mines agp by the way) gave the contacts a squirt with some co2 contact cleaner put it back in and hey presto not a problem since....cant hurt to try as im not the only person to have the same problem with the 6600 GT one of my friends had the exact same problem except his power supply was dying but the symptoms were the same