I would hold fire on overclocking especially if that involves raising the vcore on the 45nm CPU's at the moment as there are serious issues for concern.
Check out the last few pages of this thread here (E84000 thermal related issues)
Basically there have been reported cases of Sudden Death Syndrome, or "Electrodegridation" of many 45nm CPU's
Now, many people say it is due to over volting (and this is true) as the Intel Technical Specifications Datasheets list 1.45V as the absolute Maximum that the core will tolerate, it's usually wise to back down from this by a fair way due to inaccurate BIOS settings of the Voltage... or power spikes.
The other issue of grave concern is that some motherboards.. (including my ASUS P5E3) appear to overvolt certain settings @ STOCK!

The setting of concern being "FSB TERMINATION VOLTAGE"

The Intel Datasheets specify that the QX9650 CPU should have a FSB Termination Voltage of no more than 1.15V.... yet the LOWEST value I can set on my motherboard is 1.20V!

I would hold fire seriously hold fire on ANY overclocking until some sort of clarification has been made as to why so many people are having CPU's die, erratic temperatures or degradation.

I would also read the back end of the thread I linked.. and read up on the datasheets.....

Perhaps we need BIOS updates?

I don;t know, but one thing is for sure... 45nm is VERY sensitive to voltages.

John