Hi everybody  (I’ll post this article again, since I’m an expert now , at least that’s  what the Acererguy says :-) ,

I found a way to install the AHCI drivers on a Acer5920g AFTER installing Windows XP on the laptop.

In case you forgot to slipstream (using NLite) the AHCI drivers in the Windows XP CD.
Where for best performance the SATA-HD uses AHCI mode. Which Vista supports but XP doesn’t.
So this is for the ones who installed Windows XP in IDE-mode on a Vista-PC or Vista-Laptop.

So assuming you installed Windows XP in Ide MODE, but you would like XP be able to run in ACPI mode:

1st) Download the following driver from the Intel site:
http://downloadcenter.intel.com/Product_Filter.aspx?ProductID=2101&lang=eng

Nr. 1. “Intel Matrix Storage Manager iata82_cd.exe” (where 82 is the version nr. at moment of writing this)
Nr. 2. “f6flpy32″ (zip/rarfile) This one is the drivers you normally need for the “F6 mode” when you install
Windows XP.

2nd) Open file NR. 2. and extract the whole folder to wherever you like. Make sure you remember the location.
Copy from this folder file “IaStor.sys” to C:\windows\system32\

3rd) Copy the following registry file to your desktop (copy and paste it into notepad) and save as “ahci.reg” (Only copy-paste what is italic between the lines below)

———————————————-

Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\CriticalDeviceDatabase\pci#ven_8086&dev_2922&cc_0106]
“Service”=”iaStor”
“ClassGUID”=”{4D36E96A-E325-11CE-BFC1-08002BE10318}”
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\iaStor]
“Type”=dword:00000001
“Start”=dword:00000000
“Group”=”SCSI miniport”
“ErrorControl”=dword:00000001
“ImagePath”=”system32\\drivers\\iaStor.sys”
“tag”=dword:00000019
“DisplayName”=”Intel AHCI Controller”
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\iaStor\Parameters]
“queuePriorityEnable”=dword:00000000
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\iaStor\Enum]
“0″=”PCI\\VEN_8086&DEV_2922&SUBSYS_B0051458&REV_02\\3&13c0b0c5&0&FA”
“Count”=dword:00000001
“NextInstance”=dword:00000001

———————————————-

4th) Go to This Computer-> Properties -> Hardware -> Device manager.
Under IDE ATA/ATAPI-Controllers, right-click the first INTEL(R) Controller, and update the driver.
Manually install the driver!! Make sure in every step you choose  manually yourself what drivers to install!!
Browse to the folder where you extracted file NR. 2.: “f6flpy32″.
Now choose the “iaAHCI.inf” to install. All the AHCI drivers will be installed now.

5th) Double check you’ve copied the IaStor.sys file as part of step 2. Now do the following:
Run the “ahci.reg ” file to add the entries into the registry.
Reboot the computer and enter the BIOS.
Change the setting for the onboard Intel controller to AHCI, save and exit BIOS.
Boot into Windows.

6th) Windows will startup because of the manually installed drivers in step 4.
Windows will find new hardware and install drivers automatically
(because you changed the original driver manually in step 4, windows wants to restore this driver).
Just ignore this and go to the Nr. 1. file: ” Intel Matrix Storage Manager iata82_cd.exe “.
This is a setup file. Run this setup and the “Intel Matrix Storage Manager” will install the complete AHCI-SATA driver.

After installation:

Restart!

God bless you all,

Sparkion