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Windows 7: AHCI : Enable in Windows 7 / Vista

05 Mar 2013   #510

64-bit Windows 10 Pro

Ah, ok. No problem.

..I meant.. :
.. now in my written -SATA operation [ACHI]. When I'll do a "clean install Windows 7", a) will bios stay like it is now or I have to care about?
Your BIOS settings will stay set.
..and b) maybe (not sure), I'll update my bios from A13 to A19, then will I have to look for.. or settings will stay?
(never I did something else than restoring to factory excuse my simple questions...)
Sometimes flashing (updating) your BIOS firmware will reset the settings back to default, so you should double check them to make sure they are still set how you like afterwards.
For admin.
-Is it possible someone to write in his "system spec" about two computers? Often I see confusion when I get a reply..
There's just not enough room to have multiple "separate" system specs. However, if you have enough space, you could still type in the other systems specs within the same fields separated by say a dash.

It would be best to specify in the post which one you are having the issue with to help avoid confusion though.

My System SpecsSystem Spec
05 Mar 2013   #511

Windows 7 Home Premium x64, *W7 Prem. x64

so many "things" about computing ...are getting clear!... many...."well made".....tutorials....
......You are ...REALLY......valueable!
My System SpecsSystem Spec
05 Mar 2013   #512

64-bit Windows 10 Pro

You're most welcome notis. :)
My System SpecsSystem Spec
08 Mar 2013   #513

Windows 7 Pro 64 bit SP1
Wow that was a lot of posts !! 52 pages !

Hello all !
Just registered because I want to add my 2 cents worth on this topic, and get your views on my BIOS issues and registry values on my Win 7 Pro SP1 64.

I have been following this thread since the 2010 posting, and I see it's still going strong.
I have a fairly new Dell Studio XPS 8100, and a SATA Seagate internal hard drive, with a LaCie external eSATA backup. (1 TB SGate and 2 TB external).

In trying to determine whether or not I was in IDE or AHCI mode or whatever, I checked the registry and found that the values were for msahci = 3 instead of 0, and also the iaSTorV = 3 instead of 0.

So getting into the BIOS (America Megatrend?) the only setting options I found was ATA or RAID, and RAID was selected .. showing SATA 1 Drive, SATA 2 Drive, etc.

Now previous post here indicated that if RAID is selected, even though I do not have more than one internal HDD and is not really set up in RAID fashion, that it automatically puts the system into AHCI mode, and ATA would be IDE mode, if I am correct.

So what I would like to know first, why is the registry showing 3 instead of 0, and SHOULD it still be changed to 0, or left at setting 3, and secondly, if I were to install a SSD, would it work in this RAID selection mode (assuming it is AHCI also) .

By the way I did check in Command Prompt that the TRIM is activated (defaultdelete = 0).

Thanks for any advice or insight anyone might be able to give on this combination.
The computer is about 1.5 years old, so I figure it is FAIRLY up to date ... but these days .. even 6 months is almost obsolete !
My System SpecsSystem Spec

16 Mar 2013   #514

Windows 7 Enterprise (x64); Windows Server 2008 R2 (x64)

You can change both "msahci = 0, and also the iaSTorV = 0" it will not hurt anything. If you are adding a new drive I would make sure both are set to zero. They maybe set to 3 because you are using another AHCI driver. RAID is the correct setting it will be RAID if you have one setup and AHCI if there is no RAID. -WS

Old thread.
My System SpecsSystem Spec
16 Mar 2013   #515

Windows 7 Pro 64 bit SP1

Thanks for your reply WindowStar. I will make the settings you suggested. ZGZ
My System SpecsSystem Spec
05 Apr 2013   #516

Windows 7 Home Premium 64bit

Wow Excellent tutorial. I am nervous around anything Registry, (I know back it up) but I am. This tutorial was spot on. Im going to put a link to it over at AVSIM. SSDs are getting some attention in the FSX community So far I love mine.
My System SpecsSystem Spec
13 Apr 2013   #517
Bare Foot Kid
Microsoft MVP

W 7 64-bit Ultimate

Hello jetblst, welcome to Seven Forums; pleased I could be a help!
My System SpecsSystem Spec
12 Jun 2013   #518

Windows 7 Home Premium x64

My Value for start was already set to 0. So I can just change the setting in the bios right?
My System SpecsSystem Spec
13 Jul 2013   #519

Windows 7 Ultimate x64

step 3 ... cilck "Exit"

note, the click is mispelled. great tutorial, though. :)
My System SpecsSystem Spec

 AHCI : Enable in Windows 7 / Vista

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