Random Crashes

[Ripley1]

Civ 3 seems to be a fun game if it didn't crash on me so often. It will crash, like I said, randomly. Sometimes I can play for 20 minutes without crashing, or it does right after i load a saved game. It also crashes when i retire and it does the world history map. It only doesnt seem to crash when im in the city screen, hasn't yet. Any other point it has.
I've done everything to fix this. I installed the newest patch, reinstalled direct x 8.0, reinstalled my video and sound drivers(checked for updates), changed graphic settings to every different setting to see if one wouldnt crash it, reinstalled the game, turned off animations, sound, and no other programs were running.
my system has a 900mhz t-bird, 640 mb ram, windows me, winfast geforce 2 mx 64mb card, ibm sound card, plenty of hard drive space, so all the specs are good but I have no clue why this game keeps crashing. Do I have a defective CD or what?