BSOD and boot failure with new build?

Hi

I am in the process of building a new PC and have run into a problem where it starts and POST,s perfect every time without fail but upon trying to boot windows, right at the point where the Windows logo first appears(Win7)
the system crashes with a BSOD.
i have tried...
: reinstalling win7 with similar result (go,s thru "windows is loading files" but crashes upon trying to display windows logo)
:booting into safe mode (same result)
: running memtest86 from usb stick (it boots,shows options screen but crashes and hangs upon trying to start the test?

Even bare bench testing with only M/B,CPU,PSU,HD and RAM does same thing?

The Cpu is listed as supported on Asus website but the RAM i am using is not on the QVL?
I have tested both the RAM (which is brand new) and the HD used on another PC and they pass fine.

The build specs are

M/B: Asus p7h55-m le
CPU: intel i5 650 (clarksdale)
GPU: IGP
RAM: Kingston 4GB DDR3/1600 (KVR16LN11/4)
PSU: Apower 720w (24pin/4pin)

Hope someone can help as i am out of ideas as to what it could be that is going wrong and naturally i dont want to replace anything until i know what the problem is?

Thanks in advance