could be an overheat prob, and also check your vid drivers (very important) and your sound card drivers. those things can really make ur puter go nuts.
BF2 is like the biggest fuckup EA ever made. i had alot of trouble runnin it for a while and im WAY above spec on my pc.
im runnin an Alien ware Area 51 3.8ghz, 2 meg ram, gforce 6800ultra (256meg) vid, sound blaster 2 autiougy (sp), after market cooling system. and i was havin game crashes like a fuck on my computer. but till i got it workin i went thru about 5 or 6 different sets of vid drivers, and uninstall reinstall the game about 20 times and messed with vid settings and stuff and i finally got it to work. as for any other games out there i have no trouble runnin them on highest vid settings resolution 1024x768 4x antialiasing and 16x anistropic filtering. BF2 is a FUCK to get it to work right. some ppl it didnt give any trouble to and some it did. sry for kinda rambling hahaha.
but yeh check make sure u have enough air flow thru ur case, if need be take the side off and put a fan on it. and try updating your sound and vid drivers. do the vid ones first cause that is the most important. here is a link to a bunch of different drivers www.guru3d.com and they have alot of other cool utilities there also.