all are DDR2
Ouch, that's aweful. Rule out the X1600 pro as it's slower than the 7600GS and costs more. A 7600GS is about like a X1650 pro GDDR3. An X1600 pro is about liek a 6600GT. I'd think the 7600GS would usually beat the 8500GT, although not by much overall. Anyway, of those cards, the 7600GS, but don't expect too much.