Amd has a 1600ghz HTT on the 754 platform and 2000mhz on the 939 (including DDR's double data rate.) It is like a FSB but is extremly fast and efficient. It is the link between the memory controller and ram (as you know)
Anyway, to make point of this post, increase in HTT speed over 754, 939 and soon to be 940 is not very different in real terms speed. But you should get the socket 939 cpu over a 754 as it will be 2 genereations old this summer.
Cisco CCNA, Comptia A+, 1/3 through CCNP