I used the NT 6.x fast installer to install windows 7 ultimate 32-bit to an external hard drive. This all went fine, and it ran on my laptop fine (after I moved it to a USB 2.0 port rather than a USB 3.0 one).
Then, since I have 8GB RAM, I decided to re-install with the 64-bit version of Win7 ultimate. Then when I tried to boot from my laptop, I got BSOD 0x7B during boot. After much trial and error, I found out that I could boot it by changing the SATA mode to IDE. However I want to be able to leave my SATA mode on AHCI (for the other OS). So I tried many different methods (most only differing slightly) to change to AHCI. These methods mostly consisted of changing the msahci service to Start=0.
No matter what I do, I still get BSOD 0x7B when in AHCI mode. I have tried adding my device to CriticalDeviceDatabase, to no avail.
What could be causing this, and how do I fix it?
Note: I followed the exact same installation procedure for the 32 and 64 bit versions. It beats me as to why the 32-bit version worked.
Edited by Skux, 21 January 2014 - 07:36 AM.