well ur going to overclock so i'd go with the G.SKill 2x1GB Dual Channel PC 4000, dont wry about compatibility, it will get downclocked to PC 3200 Speeds, but when you OC you'll be able to OC it higher than a original PC 3200. by 50Mhz *2=100Mhz, so thats also 50Mhz on the CPU FSB speed, and x the amount multipliers, its around 600-800MHz increase.