# Enabling AHCI on Windows 7 systems with AMD



## de.das.dude (Nov 15, 2011)

I didnt know of this till today.
this thing rocks. i am getting read/writes of excess of 100MB/s on my 4yr old 80GB itachi and the 500GB WD!

be sure AHCI is disabled in your BIOS

1. Goto start.
2. Type regedit.
3. Click on regedit.exe
4. Follow this path: HKEY_LOCAL_MACHINE>system>CurrentControlSet>services>msahci






*Open HKEY_LOCAL_MACHINE






Open system





Open currentcontrolset





Open services





Open/Select msahci





Select start





Right click and select modify





Put in the value 0 in the selected region





Press OK and exit regedit.
*​
5. Reboot into BIOS.
6. You will find AHCI under SATA configuration or something like that.
7. Enable AHCI mode on one group. Connect all HDDs to this group(enable other groups if necessary). Note Optical Drives may/may not work with AHCI.
8. Save BIOS settings and reboot into Windows.
9. Windows will ask to restart to apply changes. Do EET!!
10. After rebooting, goto your motherboard product page and download the latest AHCI/RAID driver.
11. Will probably be in a zip file. extract it to some C:\temp (say)
12. Open Device Manager.
13. Click on the IDE/ATAPI controlers.
14. Select the AHCI controller ( it will be named AHCI<something>)
15. Right click, select update drivers
16. Select "Browse my computer for software" Option.
17. Point to the c:\temp folder which contains drivers. Press ok. Your Drivers will be automatically installed.
18. Reboot as necessary.
19. Enjoy new write Speeds.
20. Spread the love


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## itsakjt (Nov 15, 2011)

You wrote and presented all the instructions super awesome


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## _JP_ (Nov 15, 2011)

Not that there isn't any info about that on the internet, but still very good job. 
In my case, I have still to find a way to enable AHCI on (mobile) platforms with nVidia chipsets.


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## Daimus (Nov 15, 2011)

Microsoft have program Microsoft Fix it 50470. It enables AHCI automatic. 
http://go.microsoft.com/?linkid=9741862


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## claylomax (Apr 27, 2012)

Daimus said:


> Microsoft have program Microsoft Fix it 50470. It enables AHCI automatic.
> http://go.microsoft.com/?linkid=9741862



I forgot to install the AHCI driver during my last Windows intallation and now I want to enable AHCI mode.
Do I need the driver to enable AHCI mode in the bios? and what happens if I enable AHCI mode without the driver?
What's the difference with the AHCI driver my motherboard ships with?


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## OneMoar (Apr 27, 2012)

you should not need todo anything other then enable ACHI in the bios and possibly install the chipset drivers ... on windows 7 at least
the absolutely worst thing that's gonna happen is that it might not boot in achi  mode ... there's a registry fix for that iirc


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## newtekie1 (Apr 27, 2012)

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\pciide

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msahci

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStorV

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor

I believe these cover Intel, AMD, and nVidia(not totally sure on nVidia).  Just change the Start value in each of these to 0.  Also, this allows you to go from AHCI to RAID as well.



OneMoar said:


> you should not need todo anything other then enable ACHI in the bios and possibly install the chipset drivers ... on windows 7 at least
> the absolutely worst thing that's gonna happen is that it might not boot in achi  mode ... there's a registry fix for that iirc



Even with Win7 it sometimes won't boot.  This is the registry fix.


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## Easy Rhino (Apr 27, 2012)

ok, sorry this has always confused me. could somebody give a layman's answer to what AHCI is and how is differs from RAID and other things in the bios? Also, why would I need to disable AHCI in bios but enable in Windows??


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## Athlon2K15 (Apr 27, 2012)

The Advanced Host Controller Interface (AHCI) is a technical standard defined by Intel that specifies the operation of Serial ATA (SATA) host bus adapters in a non-implementation-specific manner.

The specification describes a system memory structure for computer hardware vendors to exchange data between host system memory and attached storage devices. AHCI gives software developers and hardware designers a standard method for detecting, configuring, and programming SATA/AHCI adapters. AHCI is separate from the SATA 3Gb/s standard, although it exposes SATA's advanced capabilities (such as hot swapping and native command queuing) such that host systems can utilize them.


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## OneMoar (Apr 27, 2012)

this is what yeilds the most gain with AHCI enabled
http://en.wikipedia.org/wiki/Native_Command_Queuing


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## Daimus (Apr 27, 2012)

claylomax said:


> I forgot to install the AHCI driver during my last Windows intallation and now I want to enable AHCI mode.
> Do I need the driver to enable AHCI mode in the bios? and what happens if I enable AHCI mode without the driver?
> What's the difference with the AHCI driver my motherboard ships with?




As far as I know, the native driver offers better performance and compatibility than standard driver is windows. It is better to download the latest driver from the official website of the motherboard manufacturer.
Then you need to run Microsoft FixIt, which would make the necessary changes to the registry automatically.
You must then reboot and enable AHCI in the BIOS. 
If you enable AHCI in the BIOS  without changing the registry, then when you boot, you will get the message "OS not found" or something like that.


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## Derek12 (Apr 27, 2012)

That was very nice, because before that I couldn't enable AHCI in BIOS for my netbook, or Winows would refuse to boot

Many thanks


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## Daimus (Apr 27, 2012)

Easy Rhino said:


> ok, sorry this has always confused me. could somebody give a layman's answer to what AHCI is and how is differs from RAID and other things in the bios?



It is strongly recommended to enable AHCI if you are using SSD (of course, if you want it to work more than a month and show the best performance). In addition, AHCI allows "hot swapping" drives without turning off the computer and some other functions.


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## Easy Rhino (Apr 27, 2012)

Daimus said:


> It is strongly recommended to enable AHCI if you are using SSD (of course, if you want it to work more than a month and show the best performance). In addition, AHCI allows "hot swapping" drives without turning off the computer and some other functions.



what if i have just a regular platter type sata 3 drive?


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## newtekie1 (Apr 27, 2012)

Easy Rhino said:


> what if i have just a regular platter type sata 3 drive?



It is still a good idea to enable AHCI, as it gives the system access to most of the advantages SATA offers such as NCQ and Hot Swapping.  It won't make a huge difference, but still worth it.  In fact, I think Native Command Queuing only really helps with traditional hard drives.


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## de.das.dude (Apr 27, 2012)

claylomax said:


> I forgot to install the AHCI driver during my last Windows intallation and now I want to enable AHCI mode.
> Do I need the driver to enable AHCI mode in the bios? and what happens if I enable AHCI mode without the driver?
> What's the difference with the AHCI driver my motherboard ships with?



the driver that comes with windows isnt really good.
the one that comes with the motherboard shows the real performance, well, thats what i have heard.


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## Drone (Apr 27, 2012)

That registry trick won't work with recent drivers, it bsods, however I didn't try Microsoft's fixit tool


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## CaptainFailcon (Apr 27, 2012)

Drone said:


> That registry trick won't work with recent drivers, it bsods, however I didn't try Microsoft's fixit tool



Hmm try installing the native chip-set drivers before changing the key


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## suraswami (Apr 28, 2012)

I have to try the recommendations.  Nice post.


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## chudddds (May 2, 2012)

worked for me on a :

ASUS CM1740 Desktop
ASUS A75-M mobo
Win 7 Home Prem 64 bit

got the latest bios from asus

latest ahci driver package from amd

no problems at all  

thanx OP


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## chudddds (May 2, 2012)

*Works for my DVDRW also !!!!*



de.das.dude said:


> I didnt know of this till today.
> this thing rocks. i am getting read/writes of excess of 100MB/s on my 4yr old 80GB itachi and the 500GB WD!
> 
> be sure AHCI is disabled in your BIOS
> ...




just to add to your note about optical drives, it worked for mine:

DH24ABS (thats a rebadged model number for a LiteOn)

ASUS CM1740 desktop
ASUS A75-M mobo (FM1)
Win 7 home prem 64 bit

new bios from asus, new ahci drivers from amd, worked flawless !!!!!!!!

brought my sata controller drivers up to Jan, 2012


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## FishHead69 (Apr 18, 2014)

Cheers de.das.dude . Worked a treat 

I know it's a old thread , but had to bump 

Cheers


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## eidairaman1 (Apr 18, 2014)

Shoot before i even installed windows id set Ahci on  install windows and installed chipset drivers


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