Change valors HDD IDE AHCI Windows 7

After seeing a post of other forum member about switching between different modes i decided to post about the registry changes which allow you to switch between Ide, Ahci and non-member raid modes in windows 7 using a single disk without re-installing and showing the performance differences.

It should also work in vista, i dont know if it works in xp but someone could test it out.

First backup/image all your information incase anything goes wrong but it is just a matter of 3/4 registry changes which are easily reversable.

Go into the registry using regedit and change each of the “start” values in the registry keys below from 3 to 0 and this will allow you to change between the different modes by just changing the option in your bios each time you reboot.

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\servic es\pciide

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\servic es\msahci

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\servic es\iaStorV

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\servic es\iaStor

You might not have the last registry key (iastor) as this is installed in the registry with the intel raid drivers, the default windows 7 raid driver uses the iastorV key.

These are some pics of the performance differences for me, the first pic is running in Ide, second is Ahci, third non-member raid.

For me non-member raid is the best performer but the wiper is too slow in this mode. By easily changing modes in the bios any time i want to run the wiper i can switch to ide/Ahci mode run it and reboot switching back to non-member raid. 🙂