Later sockets like socket 939 have more pins on them so therefore there is more overall data throughput so baiscly yes it does make a difference. But then its difficult to compare sockets like socket A and socket 478 because different CPU's run in them. Basicly, the more pins, the more data throughput, therefore higher performance. But it depends on if the cpu utilises the socket or not. The 939 3200+ wouldnt utilise the sockets bandwidth as much as a 939 4000+.
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