Tutorial : How to switch from IRRT to AHCI mode - E6400/E6500 (Vista)

This tutorial doesn't work in our Company at Latitude E6400

 

IMSM is crap. Don't use it unless you have two HDDs in your computer set up in a RAID array.

It's much better to use Microsoft's msahci driver. After I removed the junk IMSM and changed to msahci, I notice a big speed increase in loading programs, opening files and so on, furthermore, I'm already using an SSD. For those of you using HDD, the speed increase should be much more noticeable. Raw data like reboot time reduced by 5 seconds, from 35 to 30. So it's not just a false feeling.

 

Thanks for the tutorial! It took only 10mins to complete it. Now I'm running my vista business 64-bit in ahci-mode and the sound problems are gone
Edit: Forgot to mention that my machine is precision m4400

 

You have the PM45 chipset?

I was just going to post to ask if anyone knows whether the same trick works for PM45 chipset that is in my M4400, but seems you you already answered this. Will try tonight. Thanks, all.

 

can someone tell me if I should switch to AHCI or not? I have the latest bios A20 and Win 7 Ultimate. was this useful only with vista?

 

Which mode are you using now? If IRRT then I would not bother to change.

John

 

I have AHCI right now. I thought with a bios reflash it would reset everything to default.

I guess I'll just leave AHCI then. I don't think it really makes a difference with Win 7.

 

AHCI is fine. ATA loses some functionality while IRRT is AHCI with some extras that most people don't use.

The BIOS won't change this setting since it would leave many users with a BSOD when the computer starts. In fact, I don't thing the Dell BIOS updates change any of the user-selectable settings.

John

 

I had a big problem changing from IRRT to AHCI. None of the methods I tried work. I just decided to reinstall Windows and everything. It's worth it. You can feel the difference, even if you're using an SSD. My boot times almost got cut in half and the programs started popping out in an instant like the videos I see in you tube. IRRT waste CPU cycles and lags because it constantly looks for a any RAID possibility even when no other drives are connected. I read it tries to anticipate any drive that might e plugged in at anytime. How true this is I don't know, what's sure it data access speed definitely improved alot.

 

I did the following on my M4400:
1. DL'ed (from Dell) the intel storage driver and unpacked it into C:\Dell\Drivers\Rxxxx (can't remember the exact number) .
2. Booted up with the W7 install disk.
3. Chose my language.
4. Chose Repair
5. Chose Load Drivers, and browsed to the C:\Dell\Drivers\Rxxx folder mentioned above and chose "iastor"
6. Loaded the drivers (you click again Load Drivers...)
7. Chose the top alternative "Repair System" or something like that.
8. Clicked Finish when the repair was done.
9. Rebooted, twice I think.

This worked fine for W7, now I can boot up both in IRRT and AHCI, as I choose...

Oh... and I listened to Black Sabbath (mark I) all the time while doing this, I think that is a crucial ingredient