Tutorial: How to switch from IRRT to ACHI for Dell Precision M4600

Preface: I was trying to backup my new Dell Precision M4600 with Paragon Backup & Recovery Advanced 2011 Free Edition. Unfortunately, I could not get it to execute with the given bootCD. I asked that question but got no answers.

I then started google to figure out what happen. I realized it was the IRRT mode that was causing problems. However, I foolishly tried to change to ACHI mode and it caused BSOD. I searched further and found MS KB article but it did not quite address my problem. This following article was a lot more informative as well as notebookforum's own thread back in 2009. Unfortunately, they're system specific due to hardware ID & instance ID. Therefore I took another HDD and installed Windows 7 64-bit on it, then followed.

In the end, I managed to create our M4600 specific registry key. The steps are

1. Backup your system, set a restore point please. In case things go wrong.
2. Download the Intel Rapid Store Technology Driver from support.dell.com.
3. Install/extract iaStor.sys to your Windows\System32\Driver
4. Copy/paste this registry key and execute it

Code:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CriticalDeviceDatabase\pci#ven_8086&dev_1c03&cc_0106]
"Service"="iaStor"
"ClassGUID"="{4d36e96a-e325-11ce-bfc1-08002be10318}"

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msahci]
"Start"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor]
"Type"=dword:00000001
"Start"=dword:00000000
"ErrorControl"=dword:00000001
"Tag"=dword:00000019
"ImagePath"="system32\\DRIVERS\\iaStor.sys"
"DisplayName"="Intel AHCI Controller"
"Group"="SCSI Miniport"

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters]
"BusType"=dword:00000003

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Enum]
"0"="PCI\\VEN_8086&DEV_1C03&SUBSYS_04A31028&REV_04\\3&11583659&0&FA"
"Count"=dword:00000001
"NextInstance"=dword:00000001

5. Shutdown your system, go into BIOS, change your SATA from IRRT to ACHI.
6. Your system may require reboot as mine rebooted to "detect new hardware". I messed with it briefly, no BSOD, system seem to run just fine. I only tested for a couple minutes though. I did not play games or anything heavy duty to make sure. If you encounter problems, please let me know.

I included a couple of attachments. Before mod, after mod, as well as how I figured out the hardware device instance, hardware ID, etc.

If you want the registry entry, let me know, I will zip it and upload it.

 

Thanks for the guide. Saved me some serious time.

 

I have been converting our Engineering M4700's to SSD drives and needed to change from IRRT to ACHI.

Here are my registry settings:

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CriticalDeviceDatabase\pci#ven_8086&dev_1e03]
"ClassGUID"="{4d36e96a-e325-11ce-bfc1-08002be10318}"
"Service"="msahci"

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\CriticalDeviceDatabase\pci#ven_8086&dev_1e03&cc_0106]
"Service"="iaStor"
"ClassGUID"="{4d36e96a-e325-11ce-bfc1-08002be10318}"
"Security"=hex:01,00,04,90,00,00,00,00,00,00,00,00,00,00,00,00,14,00,00,00,02,\
00,4c,00,03,00,00,00,00,00,14,00,ff,01,1f,00,01,01,00,00,00,00,00,05,12,00,\
00,00,00,00,18,00,ff,01,1f,00,01,02,00,00,00,00,00,05,20,00,00,00,20,02,00,\
00,00,00,18,00,00,00,00,00,01,02,00,00,00,00,00,05,20,00,00,00,21,02,00,00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\msahci]
"Start"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor]
"Type"=dword:00000001
"Start"=dword:00000000
"ErrorControl"=dword:00000001
"Tag"=dword:00000019
"ImagePath"=hex(2):73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,44,00,\
52,00,49,00,56,00,45,00,52,00,53,00,5c,00,69,00,61,00,53,00,74,00,6f,00,72,\
00,2e,00,73,00,79,00,73,00,00,00
"DisplayName"="Intel AHCI Controller"
"Group"="SCSI Miniport"

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Parameters]
"BusType"=dword:00000003

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\iaStor\Enum]
"0"="PCI\\VEN_8086&DEV_1E03&SUBSYS_053E1028&REV_04\\3&11583659&0&FA"
"Count"=dword:00000001
"NextInstance"=dword:00000001

 

You're welcome. I'm glad my article has helped you. I was frustrated myself when I first encountered this problem.

My M4600 is still going strong, sans battery problem (already replaced once). I want to replace my M4600, but no suitable one yet. M4800 is a bit heavy, I want one like M4800, with easy parts upgrade/replacement, durable, but light. M2800, M3800, Latitude 7350 all have its pros and cons. I wish there is a good lighter hashwell version of M4800. I no longer use high end graphics as much as before, but I still need more memory and storage, plus long battery life but portable enough to take it around with me.

I also need to use 3 monitors at a time. It's so much easier to compare documents/code side by side and see the difference between them. I can drive 3 monitors easily with my M4600.