Its the amount of banks really. Anything over 4 banks seems to add a lot more stress to the NB which could be causing this issue. I have (ram in sig) and its double sided.
EDIT: Here is the link of a search within this thread for Q6600 and Q9450. You can see a few are hitting that point and past it.
http://www.xtremesystems.org/forums/...archid=5745993

