Attn. SSD owners - Enabling AHCI mode AFTER Windows 10 installation.

Toobad said:

Hello everybody. What started out as a request for guidance ended up with me solving my own problem. Thought I may as well pass on my findings anyway just in case it helps somebody else in the same situation.

So over the weekend, through a series of upgrades, I successfully hopped from Vista to Windows 10 Professional 64-bit. But, as is not unusual, I again managed to snatch defeat from the jaws of victory. With my new SSD loaded with Win 10 goodness, I realised I was still operating it in IDE mode. A confident dip into the BIOS to enable AHCI mode resulted in Windows then failing to start because it no longer recognised the boot drive! I'm guessing the AHCI driver wasn't loaded during installation since the mode wasn't in use. So back to IDE mode and a surf around for solutions. Plenty around pertaining to Vista, Win 7 and Win 8 involving changing registry values but nothing tangible for Win 10. However I found this alternative Win 8 workaround which I can confirm works equally well in Windows 10. I realise I'm probably teaching my Grandmother to suck eggs with this post here but perhaps somebody as equally technophobic as me, may find it useful. This is what I did:

1. Run Command Prompt as Admin
2. Invoke a Safe Mode boot with the command: bcdedit /set {current} safeboot minimal
3. Restart the PC and enter your BIOS during bootup.
4. Change from IDE to AHCI mode then Save & Exit.
5. Windows 10 will launch in Safe Mode.
6. Right click the Window icon and select to run the Command Prompt in Admin mode from among the various options.
7. Cancel Safe Mode booting with the command: bcdedit /deletevalue {current} safeboot
8. Restart your PC once more and this time it will boot up normally but with AHCI mode activated.
9. Bask in the reflected glory of being a total Windows 10 God

   Tip

See also: How to Enable AHCI in Windows 8 and Windows 10 after Installation

YOU ROCK! I just upgraded a Dell AIO that had a small SSD caching for a 2GB HDD. I installed a 2GB Samsung850 EVO in place of the original HDD. Restarted, all good, but realized that the controller was still set for RAID. Your suggestion on how to change to ACHI worked perfectly and saved me a ton of time. THANK YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Woodbridge said:

YOU ROCK! I just upgraded a Dell AIO that had a small SSD caching for a 2GB HDD. I installed a 2GB Samsung850 EVO in place of the original HDD. Restarted, all good, but realized that the controller was still set for RAID. Your suggestion on how to change to ACHI worked perfectly and saved me a ton of time. THANK YOU!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Hello Woodbridge. I have a similar setup with my Dell laptop. I upgraded from win 8.1 to win 10, then cloned the HDD to a Samsung 850 EVO SSD. I replaced the HDD with the SSD and it booted fine. Entered BIOS and saw SATA was set to Intel IRST. Changing to AHCI resulted in boot failure. I have tried to disable/delete the 32 GB cache m-sata SSD in Device Manager and in Computer Management\Disk Management, but it re-appears when I reboot. I think Windows keeps reinstalling it on reboot and then assumes I want a RAID setup. Is that what's causing Windows to reject the AHCI setting? Any thoughts on how to eliminate the m-sata cache drive so Windows only sees one SSD?

Toobad said:

Hello everybody. What started out as a request for guidance ended up with me solving my own problem. Thought I may as well pass on my findings anyway just in case it helps somebody else in the same situation.

So over the weekend, through a series of upgrades, I successfully hopped from Vista to Windows 10 Professional 64-bit. But, as is not unusual, I again managed to snatch defeat from the jaws of victory. With my new SSD loaded with Win 10 goodness, I realised I was still operating it in IDE mode. A confident dip into the BIOS to enable AHCI mode resulted in Windows then failing to start because it no longer recognised the boot drive! I'm guessing the AHCI driver wasn't loaded during installation since the mode wasn't in use. So back to IDE mode and a surf around for solutions. Plenty around pertaining to Vista, Win 7 and Win 8 involving changing registry values but nothing tangible for Win 10. However I found this alternative Win 8 workaround which I can confirm works equally well in Windows 10. I realise I'm probably teaching my Grandmother to suck eggs with this post here but perhaps somebody as equally technophobic as me, may find it useful. This is what I did:

1. Run Command Prompt as Admin
2. Invoke a Safe Mode boot with the command: bcdedit /set {current} safeboot minimal
3. Restart the PC and enter your BIOS during bootup.
4. Change from IDE to AHCI mode then Save & Exit.
5. Windows 10 will launch in Safe Mode.
6. Right click the Window icon and select to run the Command Prompt in Admin mode from among the various options.
7. Cancel Safe Mode booting with the command: bcdedit /deletevalue {current} safeboot
8. Restart your PC once more and this time it will boot up normally but with AHCI mode activated.
9. Bask in the reflected glory of being a total Windows 10 God

   Tip

See also: How to Enable AHCI in Windows 8 and Windows 10 after Installation

THANK YOU!!

This worked. Nothing else had... Running an AMD based mobo (Asus M5A88-M w/FX-8350: I couldn't get my new SSD to run in AHCI mode in Win7/64, no matter what technique I used. In-place upgrade to Win10 and your instructions made it work.

Regards,
Ken

Many, many thanks, your suggestion worked perfectly when I couldn't get AHCI to switch from IDE after installing a Samsung SSD. You're a lifesaver!

System: MSI Platinum X58 with Win 10 64 bit installed.

Tried this method but while trying to restart in safe mode I get "inaccessible boot device"

itzoovEr said:

Tried this method but while trying to restart in safe mode I get "inaccessible boot device"

not for me either (going Raid to AHCI)..............so I used this tutorial :

https://www.tenforums.com/tutorials/2...tallation.html

and specifically

https://www.tenforums.com/tutorials/2...tml#post722791

I bought a new XPS 8900 directly from Dell, loaded all my applications and files, then replaced the HD with an 850 Evo Pro, and was a happy camper, getting really good performance. It wasn't until I ran Samsung Magician that I found out I was in RAID mode!

The switching under Safe Mode worked perfectly, although I just used Msconfig instead of BCD command.

My Magician performance tests did improved slightly, but wasn't all that bad to begin with using RAID mode. I haven't
Optimized or enabled Rapid Mode yet, but will study doing that next.

It was Too Good Toobad.

Worked like a charm!

-My older Dell Latitude E6520 was upgraded to Windows 10 recently from win 7. Today replaced the HDD with Samsung 850 Pro and restored from image. Tinkering in the Magician software I noticed the AHCI was not enabled so i was merely getting like 500MB/s read/write performance (exponentially better than my HDD, but not full capacity of my new SSD!) Had the same "Inaccessible boot device" problems and went back and forth several times from AHCI to RAID. I went back to the original MS KB you referenced and got a better understanding of what was going on and why this solution worked/works.

T H A N K Y O U!!!