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Many tutorials explaining how to change from one mode to the other. Usually it revolves around these instructions:

Change: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci Start to 0 Change: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\iaStorA Start to 0

Start = 0 tells Windows to load the driver during boot. By the way: MSAHCI is now storahci in Windows 8.

I installed Windows in RAID mode. Because the RAID manager always pops up during boot and I don't use RAID anyways I want to switch to AHCI.

I thought I could do that by setting the startup mode of iaStorA to manual (Start=3), but then I receive a BSOD after changing the mode in BIOS. When just leaving them like they are (both services at 0) and switching to AHCI in BIOS (from RAID) I also receive the BSOD.
I can always switch back to RAID with no problem, but I would love to switch to AHCI. Any steps I'm missing?

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An answer to this question might help you:… – Ramhound Jan 9 '13 at 14:10
@Ramhound Perfect, answers my question. – Dennis G Jan 9 '13 at 14:47
@moontear - I thought it might. – Ramhound Jan 9 '13 at 15:02
Maybe you want to add an answer with the information? I don't want to delete this question as it adds some more information for further searches of other users. – Dennis G Jan 9 '13 at 15:21

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