Windows 7 - Win7U X64 crashes on setup reboot

We have a new build for a friend's Media Center, and for the first time ever with Windows 7, I am having an issue with the installation that I can not isolate.

The System:
AMD Phenom II X4 955
Gigabyte 8900GPA-UD3H
2 x Kingston HyperX Blu 4GB (2 x 2GB) DDR3 1600 (KHX1600C9D3B1K2/4GX)
4x Seagate 1.5GB SATAII ST31500341AS (in RAID 5)
LITE-ON SATA CD/DVD Burner (iHAS124-04)
Windows 7 Ultimate SP1 X64

We tried installing to multiple system drives, and they all end up completing the installation, rebooting, but reboot just as the flag starts to cycle in. no BSOD, no error messages, just reboots every time. Safe mode gets as far as achix64s.sys, (which leads us to think some kind of drive/er or controller issue) then reboots.

We have tried:
setting the BIOS to all available combinations of RAID, AHCI, and IDE modes
Updated drivers (even though Windows 7 has recognized all the drives right off)
isolated all the memory sticks 1 by 1
different cables, drives, and PSU
swapped the mouse pad, just in case...

We also each went over it separately to eliminate potential PEBKAC, but each got the same results.

I desperately want to beat him about the head for trying to save $110 by going AMD instead of Intel, but to be fair I have to inquire of those that may be more knowledgeable regarding AMD installation issues...

Well achix64s.sys is the amd ahci compatible controller. I'm not an expert, by any means, but I would try leaving off the dvd burner and having the windows 7 installer install the driver from here: GIGABYTE - Motherboard - Socket AM3 - GA-890GPA-UD3H (rev. 3.0) during the installation if taking the dvd burner out doesn't resolve the problem.
Edit: you need to check that you have the right revision #

For clarification, this is a rev 3.1 board.

Tried both already:
Neither the drivers from the org CD or the updated drivers on the giga site changed the result.
Original installation attempt was utilizing bootable USB with the drivers integrated. When the install ended up in a reboot loop, we disconnected all units but the system drive, so it would appear that the DVD drive is not the culprit.

Try installing with one Hd only & 2gb of ram.

Take a look at these posts:

Common Installation Problems and Their Solutions
Questions to use for help with Installation Issues
Tutorial quick reference list for Installing Windows 7
Questions to use for help with Installation Issues