Windows 7 can't booting on AHCI but can on IDE

If your system works in IDE mode but not in AHCI mode then the following procedure should solve the problem:

1) Run the Registry Editor (regedit.exe)
2) Navigate to Registry Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci
3) Set the "Start" value to 0 (zero)
4) Navigate to Registry Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Pciide
5) Set the "Start" value to 0 (zero)
6) Shut down
7) Start up again, but before Windows boots go into the BIOS configuration screens and change the disk mode to "AHCI". Save the new BIOS configuration and restart so that Windows boots.

When Windows starts, it will detect the change, load new disk drivers, and do one more reboot to start up with them.

@sminlal.
both of them are 0 already.
because i used to AHCI before the problem occured.
i tried to use system restore, to restore the system files before the problem occured.
but still can't boot and always got stuck on starting windows (AHCI mode)
even in AHCI i can't run the safe mode got stuck when it tries to load SYSTEMPNP.sys (or somewhat like that)
but on IDE. it can run anything.
any idea?

It almost sounds like your AHCI driver may have been corrupted. You might try to use the Windows install disk to repair your installation. Sorry, I can't give you step-by-step instructions because I've never had to do it myself.

@sminlal
ok, i got the idea..
btw, you know the difference about ICE v AHCI?
i try using IDE now, and i feel this one is very bad on performance comparing to AHCI one.
or this just my imagination?

There isn't a lot of real performance difference between IDE and AHCI modes. The two modes are just different ways for the OS drivers to communicate with the SATA chipset - the raw transfer speeds over the cable to the disk drive are the same in either case. It's not as if you had an actual IDE disk drive connected using IDE cables.

so that, it's ok either way using IDE or AHCI.
there's no major issue will occur?

It should work fine in IDE mode, although the fact that your AHCI stopped working suggests you have some sort of issue that could potentially cause problems.

I have just had the same problem - i have a vertex3 ssd disk as my boot/os drive and a conventional wd disk for storing files etc.

Iv'e had no problems until this morning when it got stuck on the Starting Windows (win7 64bit) screen and never moved off. I changed AHCI -> IDE in bios and it booted. I then set it back to AHCI and...it booted!

So if, as someone else mentioned, windows reloads the AHCI drivers when booting if last reboot was not AHCI (i.e. IDE) then it could be a corrupt driver issue i guess. All i know is it's working fine now