Dell Inspiron AHCI can't detect hdd

BIOS update, EIDE card, or overlay software? (FAQ Hard disk recognition)
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BIOS Newbie
Posts: 18
Joined: Thu Dec 04, 2008 3:28 pm

I've managed to build a custom pci option rom for my Dell inspiron 9400 to switch ICH7 controler from compatible to sata ahci mode.
PCI registers looks ok but at boot time bios report my hdd as is was detected in legacy mode and now controller is switched to ahci so all programs can't access my hdd.
But if I boot into linux (from usb stick) I can see and get access to my hdd without problems.and is in ahci mode because hwid is changed to 8086:27c5.
I need somehow to let bios redetect my hdd or something else to have hdd available after bios post.
How can I do that?
The Hardware Archivist
Posts: 6286
Joined: Wed Mar 20, 2002 7:11 pm
Location: Netherlands

pretty simple. if you installed windows without ahci mode and now are trying to use it in ahci mode it has the wrong driverset loaded for that. reinstall windows and don't forget to feed it the drivers from floppy during the F6 stage of the install.

Do not assume anything

System error, strike any user to continue...
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Posts: 13
Joined: Tue Oct 19, 2010 6:30 am

i'm sorry to bring this old thread back from the dead but there are times that re-installing Windows may not be necessary when changing SATA modes in the bios and just requires some registry edits before changing SATA modes.

Microsoft published support article 922976 on how to deal with stop error messages after changing SATA modes (it mentions using Registry editor to edit a few registry values to "enable" the SATA AHCI drivers):

that article assumes that user is installing or using either Windows 7 or Windows Vista, as I experienced a similar problem when changing the SATA mode on a relative's Dell Inspiron 580 desktop PC [which has Intel 5 Series SATA controllers] from IDE compatibility mode to AHCI mode and running Windows 7.
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