Bios Mods -The Best BIOS Update and Modification Source

Help please!

I am trying to get the E5440 working with P5K SE/EPU.

I have moved on from - "unrecognised CPU, please update BIOS to release its full potential."
and I am now at "starting windows". I get the first 2 dots of the swirl and then then straight to automatic reboot.
Repeat ad infinitum (unless I let windows do a startup repair).

I have tried multiple BIOS updates

- BIOS from ASUS website and applying the microcodes for CPUID 10676,
four in total: 0016760F,0106760F, 0046760F, 0406760F

(CPUID is based on E5440 SLANS - C0 stepping)

- BIOS from Genius239 with 0016760B, 0106760B, 0046760C, 0406760C

- BIOS from Genius with all of the above eight microcodes.

I had this Xeon running on a DG31GL with absolutely no problems (zip, nada, non - Oh why O' why can life not be so simple?)

Well, anyway, the CPU works fine on that Motherboard. The only other addition to my setup is a 880 GTX OC. I do
not know if that could be adding to my problems?

Any assistance/advice would be gratefully appreciated.

Oh yes, it's Windows 7 Ultimate (64 Bit), 8GB DDR2-800

I can honestly say that I have run out of avenues to explore.

Any suggestions are welcome. Please!