Vista and ACHI mode!

[Keizer]

Still plugging away on this new PC build that I did for my brother. I was putting together a file with all the proper bios settings that I could store on his 2nd hard drive for future reference.

System specs:
*Gigabyte GA-EP45-UD3R.
*Two WD SATA 7200 rpm hard drives
*3 GHZ Intel dual core CPU E8400
*4 gigs Corsair DDR 2 800 RAM
*Radeon HD 4830
*Onboard sound

Ok, I hope I don't have to re-install Vista because of this. In the bios under "Integrated Peripherals" I have "SATA Port0-3 Native mode" set to "Enabled". This in regards to the two WD SATA drives in the system. However, under "Onboard SATA/IDE Ctrl Mode" I had it set to "IDE". I believe this should have been set to "ACHI" instead correct? And since I didn't have it set to ACHI, Vista probably didn't load the correct drivers during the install for me to switch it now?

I totally overlooked this setting in the bios. On a side note though, I get really good speeds from the two drives with that bios setting at IDE running HD Tach.

Any advice??

[Keizer]

Re: Vista and ACHI mode!

A quick update, I did go ahead and switch to ACHI in the bios. I then booted back to windows Vista, and it installed the drivers.

Where does this put me?

[Lsdmeasap]

Re: Vista and ACHI mode!

Well AHCI is up to you, it does slow boot time that is for sure. And the speed gain is negligible so if you are not using Hotswap then it really isnt worth it. But you can leave it either way in Vista really as vista has it's own driver.

But if you do plan to leave it, I would install the Intel AHCI driver as it will be better overall

[soldier]

Re: Vista and ACHI mode!

I have my ACHI set to disabled.. Like LSD said, the speed gain is negligible..

[Keizer]

Re: Vista and ACHI mode!

Ok guys, thanks for the info. I will just leave it set at IDE then. I ran HD tach and saw no speed difference.

Thanks again!!

[VorLonUK]

Re: Vista and ACHI mode!

Ok guys, thanks for the info. I will just leave it set at IDE then. I ran HD tach and saw no speed difference.

Thanks again!!

I've tried installs with both and noted the results. Using HdTune or Hdtach there is about a 30% increase in the "Burst Rate" when using AHCI.
Access times and Hard drive start & end transfer speeds appear to be about the same.

Vista supports AHCI "Out of the box" so you don't need to use the F6 install method as vista includes generic drivers which are used when you start a new windows installation and have AHCI enabled in the bios.
Once in windows, the Intel matrix storage Driver includes a windows console for quickly checking the drives are ok. Also once in windows installing the matrix driver updates the generic MS Ahci driver to the Intel one - which essentially updates it.

Also not some low level programs (often found on bootable media such as Victoria and MHDD) won't work correctly when the bios is in AHCI mode. Some windows utilities won't even reports SMART on the primary drive when in AHCI mode (including HD tune). Most newer/up to date apps, such as PcWizard and even WDC Diagnostics and Seagates (Windows Versions!) will report SMART data on all connected Hard drives.

I use AHCI, but of course it adds a bootup delay as there is a secondary bios routine that has to be loaded up at bootup after the main bios.

[Keizer]

Re: Vista and ACHI mode!

I know when I installed Vista, it was set at IDE in the bios. Today when I changed it to ACHI, Vista loaded drivers at boot up. So is it even necessary to have ACHI set in the bios to get the generic drivers during the install? Because like I mentioned, Vista installed the drivers after switching it to ACHI after the fact.

I read a few threads that mentioned their windows install would not boot if they switched it to ACHI afterward. That may have been for XP though.

[Lsdmeasap]

Re: Vista and ACHI mode!

They would be installed anyway as part of the Vista install, just not loaded as you see until you enabled AHCI. If you plan to keep it install the matrix software and it will update the drivers >>>


Ya, XP is the system that would have that Issue

[SooperHOP]

Re: Vista and ACHI mode!

I know when I installed Vista, it was set at IDE in the bios. Today when I changed it to ACHI, Vista loaded drivers at boot up. So is it even necessary to have ACHI set in the bios to get the generic drivers during the install? Because like I mentioned, Vista installed the drivers after switching it to ACHI after the fact.

I read a few threads that mentioned their windows install would not boot if they switched it to ACHI afterward. That may have been for XP though.

I have vista and it would not recognize my hard drives when i switched from IDE to AHCI (and yes it's AHCI not ACHI). and when i would try to load the drivers in bios IDE mode vista would say my hardware did not meet requirements... SO I WAS SCREWED!!! just before reinstalling vista and using the F6 driver preinstall i searched the web for awhile and found a registry fix to solve the problem.

SO IF YOUR VISTA INSTALL WILL NOT RECOGNIZE YOUR HARD DRIVES WHEN YOU SWITCH THE BIOS FROM IDE TO AHCI HERE IS THE FIX:
(can't remember the site link, i just copied the text into notpad to save for future reference)

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Consider the following scenario. In the BIOS setup of a Microsoft Windows Vista-based computer, you change the Serial Advanced Technology Attachment (SATA) mode of the boot drive to use the Advanced Host Controller Interface (AHCI) specification. You then restart the computer. In this scenario, you receive the following error message:
no boot device.....ect...ect...ect...blah blah blah...

This issue occurs if the AHCI driver (Msahci.sys) in Windows Vista is disabled. This driver must be enabled before you change the SATA mode of the boot drive.

To resolve this issue, enable the AHCI driver in the registry before you change the SATA mode of the boot drive. To do this, follow these steps:
-Exit all Windows-based programs.
-Click Start, type regedit in the Start Search box, and then press ENTER.
-Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\Msahci
-In the right pane, right-click Start in the Name column, and then click Modify.
-In the Value data box, type 0, and then click OK.
-On the File menu, click Exit to close Registry Editor.

WHY is This So???:
During the Windows Vista installation process, any unused storage drivers are disabled. This behavior speeds up the operating system's startup process. When you change the boot drive to a driver that has been disabled, you must enable the new driver before you change the hardware configuration.
For example, assume that you install Windows Vista on a computer that contains a controller that uses the Pciide.sys driver. Later, you change the SATA mode to AHCI. Therefore, the drive must now load the Msahci.sys driver. However, you must enable the Msahci.sys driver before you make this change.
This issue affects only the boot drive. If the drive that you change is not the boot drive, you do not experience this issue.
AHCI provides several features for SATA devices. These include hot plug functionality and power management functionality.

[SooperHOP]

Re: Vista and ACHI mode!

let me add quickly that this registry trick worked for me, BUT my SATA ports were not hot swapable untill i installed intel's RAID\AHCI matrix driver in vista....the same driver before that said my system was incompatible, now worked and made my ports hot swapable..

[Keizer]

Re: Vista and ACHI mode!

[quote=SooperHOP;271157] (and yes it's AHCI not ACHI).

Wow, I really fat fingered that didn't I? My bad!

[Lsdmeasap]

Re: Vista and ACHI mode!

Ahh it could happen to the best of us! I often type dyslexic!

So you all good now then right?

[Keizer]

Re: Vista and ACHI mode!

So you all good now then right?

I think so. I believe I am ready to hand this beast over to my brother. Couldn't have done it without you guys!!

I will be adding this forum to his bookmarks too!!

Thanks

[Lsdmeasap]

Re: Vista and ACHI mode!

Great to hear you are good to go! Post back anytime, and for sure let your brother know if he has issues he can stop by as well (In case he cannot get you to come over )