AHCI : Enable in Windows 7 / Vista

AHCI : Enable in Vista and Windows 7 after OS install​

   Information

AHCI Advanced Host Controller Interface makes NCQ Native Command Queing along with hot-plugging or hot swapping through SATA Serial-ATA host controllers possible; Vista was the first to offer this feature. The issue with AHCI is it needs to be enabled in the BIOS prior to OS installation; doing so after you have installed the OS will disable the PC. The reason why is Windows disables the AHCI drivers not needed durring installation.

This tutorial will show you how to enable AHCI after you have installed the OS if you didn't already have AHCI enable in the BIOS when you installed the OS.

   Warning

Changing values in the Windows registry can disable your machine; if you're not sure how to do this please post a question in this tutorial and someone will be glad to help you.

   Note

This method will also work for Windows Vista though the default DWORD string value in Vista will be "4" where it will be "3" in Windows 7.

As a precaution it would be a good idea to create a "System Restore Point" before you start this, the tutorial can be found at the link below.

System Restore Point - Create

Let's get started!
1) In the Windows start menu search box type regedit, right click the entry, click Run as Administrator, enter your user credentials for the UAC prompt, then click yes to open regedit.



2) In regedit navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services.

3) In the left pane, click on msahci, in the right pane double click on Start to modify it.


4) In the window that opens change the value to 0 (zero), and click OK.

5) In the left pane, click on iaStorV (if there), in the right pane double click on Start to modify it. Repeat step 4, and go to step 6 below.
NOTE: From: Error message occurs after you change the SATA mode of the boot drive

6) Close Registry Editor.
7) Now you'll need to restart the PC and go into the BIOS and enable AHCI. When Windows boots up, it will finish installing the AHCI drivers.



8) You will need one final restart to finish the process after the drivers are installed.

   Note

For those with nForce boards, have a look at the Information post below.

The method was worked out by Everlong and credit for that goes to him, thanks mate!

Enjoy!

Related Tutorials

---

• How to Enable AHCI in Windows 8 and Windows 10 after Installation
• How to Enable HIPM and DIPM for your SSD and HDD in Windows 7

 

[matrixgaby]

I thinking something.
It is a problem that one of my HDD and one of my dvd-rw is PATA?
Anyone run AHCI with PATA drives? Will AHCI mode with PATA drives?

 

[Bare Foot Kid]

I thinking something.
It is a problem that one of my HDD and one of my dvd-rw is PATA?
Anyone run AHCI with PATA drives? Will AHCI mode with PATA drives?

Hello again matrixgaby.



In my current system I have PATA optical drives and SATA HDDs.

Your OS boot HDD must be (non RAID) SATA.

 

[ZaLiTH]

I thinking something.
It is a problem that one of my HDD and one of my dvd-rw is PATA?
Anyone run AHCI with PATA drives? Will AHCI mode with PATA drives?

Hello again matrixgaby.



In my current system I have PATA optical drives and SATA HDDs.

Your OS boot HDD must be (non RAID) SATA.

Hmmm... Well, it was just a thought. I'm only running SATA devices in my tower (4x HDD, 1x DVD-RW), so I wasn't sure if it would make much difference.

 

[matrixgaby]

My boot device is SATA non-RAID.
I will try to unplug the PATA devices, enable AHCI and see what's happening.
Also, please excuse if I make spelling mistakes, I'm not an english native speaker.

Later edit:
I remove the PATA HDD from my system and put a 500 GB Samsung F3 SATA. After that I was able to enable AHCI and boot properly.
It appears that if you have an PATA HDD in the PC, you can't enable AHCI.

 

[Stabby]

Hi,

I have an X25-M that I'm having trouble using with AHCI (Gigabyte EX58-UD3R). I managed to install the driver in Windows XP which worked perfectly. I'm now using Windows 7, and although AHCI mode seems to be enabled in the OS - whenever I boot the system/board with AHCI enabled it just says

"Port-00: No device detected"

So at that point, I can't even enter the Bios settings so I'm forced to do a CMOS reset. Also, I'm a bit confused in Device Manager. What I have listed right now are:

ATA Channel 0
ATA Channel 0
ATA Channel 0
ATA Channel 0
ATA Channel 1
ATA Channel 1
ATA Channel 1
ATA Channel 1
Intel(R) ICH10 Family 2 port Serial ATA Storage Controller 2 - 3A26
Intel(R) ICH10 Family 2 port Serial ATA Storage Controller 1 - 3A20
Standard Dual Channel PCI IDE Controller
Standard Dual Channel PCI IDE Controller

I downloaded the iaAHCI driver for ICH10R (I think that's compatible with my MB) however if I try to update the driver (via 'Have Disk') with the .inf it always gives me a BSOD. Tried updating the following:

Standard Dual Channel PCI IDE Controller
Intel(R) ICH10 Family 2 port Serial ATA Storage Controller 2 - 3A26

When I had Windows XP installed, the only drives that were visible in Device Manager was my main AHCI drive. It actually didn't display my other drives. They were still visible and accessible in explorer though.

I'm all out of ideas so...

 

[Bare Foot Kid]

Hello Stabby, welcome to Seven Forums!



I actually have Windows 7 installed on the same SSD as you with AHCI enabled.

How many HDD/SSDs are installed in the system?

 

[Stabby]

Thanks Kid

I only have the one SSD. I have another three SataII HDD's installed (all the same make, WD640AAKS). I never really bothered to select which Sata ports to plug them into, I just shoved them all in without any particular order :huh:

I thought that the order could be one of the problems, but then I start scratching my head because it seemed to boot okay in XP (and I hate having to take out all the drives again!)

 

[Dave76]

Welcome to Seven Forums Stabby.

You don't need to take the HDDs out, just un-plug the SATA cables.

The best way to install Win7 on a SSD is to un-plug all other HDDs, leave the DVD plugged in (port4 or 5) if you need it (install from USB drive?), be sure to plug the SSD into port0.
Be sure your SATA AHCI is setup correctly in BIOS, enabled for all ports, since you have all SATAIIs HDDs.

It's best to have the SSD completely wiped, no formatting, no partitioning, just as it was out of the box. Win7 will detect the SSD and align the partition, disable the minimum processes.
You will need to confirm all of the required SSD tweaks are done.

 

[Bare Foot Kid]

Welcome to Seven Forums Stabby.

You don't need to take the HDDs out, just un-plug the SATA cables.

The best way to install Win7 on a SSD is to un-plug all other HDDs, leave the DVD plugged in (port4 or 5) if you need it (install from USB drive?), be sure to plug the SSD into port0.
Be sure your SATA AHCI is setup correctly in BIOS, enabled for all ports, since you have all SATAIIs HDDs.

It's best to have the SSD completely wiped, no formatting, no partitioning, just as it was out of the box. Win7 will detect the SSD and align the partition, disable the minimum processes.
You will need to confirm all of the required SSD tweaks are done.

Thanks Dave for the help.

 

[Stabby]

Thanks Dave,

I didn't think SSD's needed tweaking for Win7 as they align to 101mb? I'll try plugging it into Port-0 as you say, makes sense.

 

[Dave76]

Your welcome.

You can find a lot of opinions on the tweaks for a SSD.

Main ones Win7 will take care of, turn off defrag, is important and worth checking.

Some people will move the default download folder location to a support HDD.

Let us know how it goes.

 

[Bare Foot Kid]

Your welcome.

You can find a lot of opinions on the tweaks for a SSD.

Main ones Win7 will take care of, turn off defrag, is important and worth checking.

Some people will move the default download folder location to a support HDD.

Let us know how it goes.

I don't install or download ANYTHING to the SSD this go round.

 

[Dave76]

I don't install or download ANYTHING to the SSD this go round.

Does your software run faster than pre-SSD, when installed on your HDD?
I have 'most' of my software on the SSD.

What do you do with or set these to?

Page file

System Restore

Shadow copy

SSD 'Enable write caching on the device'

SSD 'turn off Windows write-cache buffer flushing on the device'

User profiles and document folders

 

[Bare Foot Kid]

Does your software run faster than pre-SSD, when installed on your HDD?
I have 'most' of my software on the SSD.

Hello Dave.

I'm not seeing much difference one way or the other.

I allowed Avast, MBAM and Office 2010 to install to the SSD; I ran an Avast and MBAM scans last night and I was surprised at how fast they scanned all my stuff.

What do you do with or set these to?

Page file

System Restore

Shadow copy

SSD 'Enable write caching on the device'

SSD 'turn off Windows write-cache buffer flushing on the device'

User profiles and document folders

These are all still at default, I haven't fooled around with any of that yet.

 

[Dave76]

Thanks Ted,

Was wondering the affect when running software on a HDD, didn't think it would be much of a difference.

Kept the page file, just made it a little smaller, got plenty of RAM, haven't noticed any difference there either.

Read a claim that system restore was causing a problem for Trim to function, so disabled it. Gave a huge amount of space back, which is important with my little SSD, always do my backups so will be ok. Will turn it back on after a while for a comparison.

Write caching on, buffer flushing off.

User files and download files are moved to the HDD. A lot of sites say it's not necessary, but not a big deal to set it up.

 

[Bare Foot Kid]

Howdy Dave.


This is what I have System Restore set at, sometime I use it as a "backup" if you know what I mean.

I keep these on the secondary monitor, everything goes to one of those, even stuff I used to "swap" on and off the desktop.

 

[LFB]

Working flawlessly here...

Thanks for the tip Ted..

+ rep to you

 

[Bare Foot Kid]

Working flawlessly here...

Thanks for the tip Ted..

+ rep to you

Hello LFB, thanks, I'm glad it was a help to you.

 

[Dave76]

Howdy Dave.


This is what I have System Restore set at, sometime I use it as a "backup" if you know what I mean.
View attachment 76639
I keep these on the secondary monitor, everything goes to one of those, even stuff I used to "swap" on and off the desktop.
View attachment 76640

Hi Ted,

I usually leave System Restore fairly large, normally have lots of free space available, but did turn it down low for the SSD.

I'll turn it back on in a month or two, see if there is any truth to the claim that it causes a problem with Trim.

 

[wakeboardr116]

ok I've read this entire thread and still cannot get it to work. I changed the registry value. Downloaded the drivers from dell (only had ones for vista 64bit) there is no exe file to automatically install the drivers. So I went to device manager and tried to update the drivers manually and it said the latest drivers were installed. If I choose let me decide then select have disk and point it to the driver folder it then says it installed sucessfully. So i restart my computer and change the bios settings and I get a bluescreen when windows starts loading. Then I have to do a system restore.

When in device manager and I point it to the right folder there are 2 different files I can choose from. One is iaAHCI.inf and the other is iaStor.inf. After I choose either one it then lists several different models which are like Intel ICH7, ICH9, ICH8 etc... So wich file should I choose and then how do I tell which model I need to pick?

Thanks