I need to build a PC based on AMD of course. Which cpu socket is the way to go, 754 or 939? Is it fair to compare Semprons and Athlon 64? Is a Sempron 3400+ equivalent to an Athlon 64 3200+ since both have same clock speeds and cache size? What about Turions? I heard they beat everything and only requires half the watts. Is it better to have a 1 MB L2 cache than 512 KB even if the latter has higher clock speed? For the CPUs with 1 GHz Hypertransport, I assume that's the fsb, will I need to overclock a DDR400 to 500 MHz to it's Nsync with the fsb.