Hey Intrepid I am glad it helped to bump the NB volts as that usually will help out alot when trying to stabilize memory. Sorry your HZ won't quite achieve the higher settings but,if you are able to run stable where you are at currently your system will be anything but slow!!
I always run a minimum of a 90mm fan blowing on both my memory and my Northbridge. Always... On this set up I am running a 120MM fan over both.
Is it necessary? Well I am running much faster so maybe that is part of the difference?
I say just keep prodding it an getting a little more all thew time.

WZ