How to enable AHCI/RAID mode in Windows 7 without reinstalling
I recently got a wild hair up my ass to add a RAID to my desktop. My desktop is a Gateway FX6840-23 and it came with a 1TB drive. I bought an identical drive and thought that I’d put then in RAID 0 for the increased performance, seeing as my Experience Index was only 5.9 due to a slow HDD (all other indexes were in the mid-7’s, and the drive is a 7200 RPM unit).
Digging around the BIOS I saw that the SATA controller was using AHCI mode. I cloned my current drive to another 1TB drive I had (yeah, I have 3 -1TB drives, a 500GB, and a 1.5 TB), rebooting into the BIOS and changed it to RAID. After a reboot, I hit ctrl-I and entered the RAID utility. I built the RAID and rebooted. Well, to put it nicely, I got a BSOD. I tried various things for the next 3 hours, including using Windows 7’s extended partition utility, doing a complete restore to factory on the extended partition, and everything. After I did the restore, I saw that the HDD performance hadn’t changed.
Well, I haven’t messed with RAID before on a desktop, so this was a learning experience. After some Google searches, I put the computer back in AHCI mode and booted to the clone. This worked just fine. I went to Gateway’s website and downloaded the RAID drivers.
I noticed that the driver was named iaStorV.sys, so I did a search for it and found it already installed in the Windows\System32\Drivers folder. I did a registry search for it and found it in HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\iaStorV. This made me happy!
Some more Googling later and I figured out that if I changed the REG_DWORD from 3 to 0 that it would enable things to work. I rebooted the computer, went back into the BIOS and changed the SATA controller to use RAID, pointed it to boot from the clone, and it booted right up! No BSOD, no hiccups, no nothing!
This should work going from IDE mode as well. I tried to clone the clone to the RAID, but Acronis didn’t like that too much, so I’m doing a full backup of the clone (I needed to do it anyway) and I’m going to try to restore it with the Acronis Resuce media. It’s already midnight, and this is one of those things that I’m not going to be able to put down until I’m done with it. Oh well, I guess it’s time to get back to work! Good luck getting your stuff working!