Keeping in mind that:
1. The Socket 939 is a dying species,
2. The AM2 socket will be around for quite a while, since the new AMD quad-core processors are AM2-compatible,
3. AM2 motherboards are quite cheap, and
4. DDR2 RAM is a dime a dozen these days
I'd say you're better off taking the leap from the antiquated S939 system to a brand new AM2 counterpart. Just start saving up those bucks
