I had trouble finding good drivers for my AGP ATI 3650, couple of games (Medieval II Total war, Fallout 3 ... ) used to crush my system and restart my computer, even with installed latest hotfix by Sapphire.
Until recently I found out about the Omega drivers, tried them and the games stopped crushing, but I am experiencing a little performance drawback (getting 20fps where I used to get 25fps) but I am happy playing with a bit of lag as long as I able to play at all.
So try those if you already haven't.
Cheers