Need help enabling AHCI for a Dell Optiplex 745

You mention that your computer is presently running in IDE mode, but you didn't say which setting is in use.  Is the computer already set to Normal mode?  Many Dells that use this terminology seem to use a SATA to IDE bridge so as to avoid the need for SATA drivers.  If your computer was a bit older I would say that this was definitely the case, but the oldest BIOS file I see on the Dell support page was issued in 2006.  By that date most of the Dells were fully into SATA/AHCI.  However, there are no SATA drivers on the support page for the Optiplex 745.

In order for the registry hack to allow the switch, it is necessary to have the associated AHCI driver for your controller.  Changing the registry will usually enable the driver if it is present, but it can't do anything for you if the driver is missing.

Thanks for the response.

I have the Sata ports set to the 'normal' mode.

The AS SSD benchmark shows it running in Intelide mode, device manager also showing IDE mode.

When I go into device manager > IDE/ATA/ATAPI , The driver details for my drives are 'Current Version : 6.2.8400.0' , 'Driver Date 6/21/2006'.

I believe you will have to remain in IDE mode.  Dell computers shipped with Windows XP that are AHCI capable, have Windows installed in an AHCI mode, and have the AHCI mode available in the SATA controller, show SCSI/RAID controllers for the mass storage.  The screen shot you have provided shows the ICH8 hub directly in IDE ATA/ATAPI controllers.  I would conclude from this that Windows is using the IDE drivers and that the computer has the SATA to IDE bridge I mentioned previously.  Having that translation between the operating system and the computer hardware prevents loading the AHCI drivers even if they are available on the installation disk.

Thanks for your expertise. I attempted changing a few settings. I forced AHCI mode through the device manager, but that led to the repair screen at boot. Than I started reading about slipstreaming and something about Gnite ... it was far to much work for an extra 15% boost ... if even possible with Win 8.

The Dell BIOS simply doesn't have the AHCI option, even though PCWizard does indicate it's a feature !!! Can't win them all.

Thanks for your time.

I'm sorry I couldn't be of more help.  Best of luck to you.

I too have a Dell 745 and have recently placed a SSD II drive in it.

I made no modifications to the setup.

Just when installed on it.

And it seems to be much faster.

But nowhere near the top speed I would expect with an SSD.

My question is why not use a new SATA II or III PCI express card.

I would think that would have everything we need to drive the SSD drives (mode II or III) to their full speed or am I missing something here.

Hi Don,

This is an older system so I wouldn't expect it to run that much faster. A controller card would probably improve things.

It should be compatible.

Imaging the drive isn't recommended, that could be where your issue lies.

Try setting your SSD to first boot priority in the BIOS.

Try a fresh install of WIndows 7.

Burn a copy from here, if you have a DVD-R + Burner ...

http://forums.mydigitallife.info/threads/18769-Download-Windows-7-ISO-%28Official-32-bit-and-64-bit-Direct-Download-Links%29