I need help enabling AHCI

[SickBeast]

Hi Guys,

I'm trying to enable AHCI on my MSI 770-G45 motherboard. It's an AMD 770 chipset board and I'm pretty sure it has the SB710 southbridge.

My hard drives are a 1tb Hitachi 1000.C and a 2tb Seagate Barracuda Green LP if that matters.

Anyhow, when I go into the BIOS and change the setting from "IDE" to "ACHI", Grub comes up and says that it can't find any of my operating systems (I use Grub as a boot loader; it's Linux based).

I've heard that you need to do something to the Windows registry and install a driver to make it work, but if Grub isn't even locating my OS, that gives me cause for concern.

I'd like to do this as I hear there is a bit of a performance boost involved.

Any help will be appreciated.

TIA :thumbsup::thumbsup:

 

[PascalT]

When I enabled AHCI on windows 7 I put in a different registry input before rebooting into AHCI mode. Just google it it should be easy to find. If you don't do it you won't be able to boot anymore.

 

[SickBeast]

So is it just a matter of doing that registry fix, enabling AHCI in the BIOS, and that's it?

I'm still nervous.

When I set it to AHCI, it was in the RAID controller settings. I'm worried that it's looking for a RAID array and I'm going to mess something up.

 

[Rifter]

you need to do the registry hack in windows for it to work. Linux will work fine without any fixes or at least it did for me.

 

[Drsignguy]

Its fairly simple. All you have to do is:

Go to: regedit

Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\mashci

Set the value from (most likely 3) to 0 and then reboot.

Go into Bios and make sure you have it set to AHCI and save.

When you boot back into windows it will load the drivers and then it will ask you to reboot again.

 

[mv2devnull]

you need to do the registry hack in windows for it to work. Linux will work fine without any fixes or at least it did for me.

Depends on Linux installation. It does need the ahci-driver just like the other OS. I've seen case (years ago), where the driver was not included in the "initrd image". Easy to fix though. Much easier than switching the WinXP, that was installed too.

Purely hypothetical: if there would be WinXP on such AMD 770 board, would it swap as easily to AHCI? Win7 includes the MS AHCI driver, WinXP did not.


To OP: Grub uses BIOS calls to load itself and OS. Those should work whether the official mode is IDE or AHCI. Where is the stage2 of Grub? Legacy Grub or Grub2?