I upgraded my 939 socket 3200+ to an X2 4600+ at the start of the year. There are smatterrings of stock around still, but the best you can possibly get for 939 is X2 4800+ (or the FX60?).
You're probably best leaving it while and getting a new AM3 (or intel) mobo I reckon.
You're probably best leaving it while and getting a new AM3 (or intel) mobo I reckon.