When switching from Enhanced IDE to AHCI, do you have to reinstall Windows?

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Cyrilix

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I'm currently running Windows 7 x64, and I installed it in Enhanced IDE mode on my Asus P6T SE. I heard that AHCI might give a little performance boost, so I was going to try that, but when I switch to AHCI mode and then try to start up Windows, at the end of the startup, it just bluescreens and dies on me. Do I have to reinstall Windows to get this working?

Edit: I guess I should say that after doing a bit of digging, it seems like people recommend a reinstall, as opposed to doing a hack fix, though I'm not entirely sure what the difference is between IDE and AHCI, that makes it necessary to reinstall. If someone could enlighten me on this point, that would be great.

Also, while I'm at it, I guess I'd also like to ask if there are any special drivers that need to be loaded in order to run the Intel x25-m at in AHCI mode at its peak performance, since I've seen some mentioning of having to load some kind of AHCI driver because the Windows one limits transfer rates, etc. etc. I may just be talking nonsense, but I really don't have much knowledge on this issue.
 
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Well, just an update to this thread: I did change the mode to AHCI and I reinstalled Windows. The speeds are actually much improved. There are a few changes:

-The small file size speeds ramp up much quicker in ATTO
-ATTO is showing that the maximum writes go up to 82 MB/s, and the maximum reads go up to 283 MB/s! Previously, it was capping out at about 250-255 MB/s. This is a pretty good improvement.

I didn't install any special driver... just let Windows do its thing, although if I should, please let me know.
 
if you have a secondary crontroller onboard or an add-on card you can swap the cable, set the primary controller to ahci, boot windows, install drivers, shut down, swap cable, boot windows, be happy. I've done this a few times before and the OS is always happy.
 
I've always heard that there is basically no noticable difference between the 2 (AHCI vs Enhanced IDE) in a non server environment...I tried AHCI recently and did not notice any performance differences
 
Can someone confirm with benchmarks/screenshots that there's a performance increase from using AHCI?

I've never bothered because I've always read it's either the same or worse performance for non-server environments.
 
Might as well turn it on, you need it for SATA's advanced features like NCQ and Hot Swap etc
 
What advanced features other than hot swapping and NCQ?
I don't even think people need AHCI for their external SATA devices anymore (if they ever did).
 
polonyc2 said:
I've always heard that there is basically no noticable difference between the 2 (AHCI vs Enhanced IDE) in a non server environment...I tried AHCI recently and did not notice any performance differences
Click to expand...

I noticed a performance decrease on my 939 with an nForce4 chipset, but a performance increase with my P35 chipset board.

I guess ya just gotta try it.

I don't even think people need AHCI for their external SATA devices anymore (if they ever did).
Click to expand...

If you want your eSATA to hot-swap, you do.
 
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