U do know that both the AMD 64 and FX-51 have on chip memory controllers... so in that It can't overclock well... really at all... because the other things in the system like the pci/agp cards can only handle a certain overclock...
Anandtech.com - "The big surprise here is that none of the current chipsets for Athlon 64 have a working PCI lock, whether they claim one or not. This was a complete surprise and our first inclination was to throw out the results, since speeds on the Athlon 64 are derived in a very different way with Hypertransport. However, oscilloscope results and tests elsewhere pretty much support our findings. There does not appear to be a working PCI lock on any current chipsets for Athlon 64. Certainly, this contributes to the poorer overclocking that we have seen on A64 inasmuch as on-board component frequencies and AGP bus are related to PCI bus."
check this out...
http://www.anandtech.com/chipsets/showdoc.html?i=1968
most importantly this page
http://www.anandtech.com/chipsets/sh...tml?i=1968&p=4
hope it helps...