Can faulty memory controller cause this?

I've put together a new system comprising of:

i7 860
MSI p55 cd53
2x 2gb OCZ Platinum 1333 DDR3
CoolerMaster 700W PSU
MSI GTX275

The system would post and BIOS reported all components including 4g of ram just fine, but the problem would consistantly occur when I was trying to install Windows 7; while installing the OS, or more specifically while 'Expanding Files' during the installation, I would get BSoD saying either "IRQL_NOT_LESS_OR_EQUAL" or some dll files are missing. So I then ran memtest86 for multiple passes to make sure it wasn't the bad memory; both sticks reported no errors while being tested individually or together.

So I thought perhaps it was a simple incompatibility issue so went ahead and picked up 2 sticks of Corsair XMS3 ram which I tested with memtest86 even before I tried installing Windows 7 again and found to be error free. But the exact same problem would occur still during Win7 installations.

I updated the BIOS, granted p55 boards are relatively new and i went from 1.0 to 1.1, I tried fiddling with all kind of memory settings on BIOS, but I would still get the exact same error.

So finally, I tried it with only one memory stick in DIMM slot #1 and viola, everything works just fine. No BSoD, no instability, no crashes whatsoever. It didn't matter whether I was using OCZ or Corsair ram sticks; if I had only one stick installed, it'd be fine and quite rock-solid, albeit a bit slower than it's supposed to be since it has only 2g of ram and running it on single channel mode; it passed all of the stress test. But when one more stick is inserted, it'd spin out to hell.
** The MSI mobo manual cleary states that I should be populating DIMM slot #1 and #3 in that order before any other slots are populated, so that's the slots I've been using.

So what do you guys think my problem is?
Can bad or faulty memory controller on a cpu cause only one DIMM slot to fail while working perfectly fine with the other slots?
Or does this sound like more of a motherboard problem?

sounds like u either stuffed ur dim slot or u got a bad stick of ram what hapens if u try the other stick in slot 1 does it bsod?
also what if u try the other stick in slot 3 does it bsod
also have u tried just running them in slot 1 and 2
i have had bad memory slots on motherboard before not much u can really do about it either replace mobo or just use other 3 slots (if its the mobo)

Try manually setting BIOS to the memory specs instead of using "auto"

If that fails, increase voltage in steps up to a max of 1.65 (if you're not already there).