XPS 13 9305 - Cannot set AHCI in UEFI

hmm, try booting the system into safe mode, reboot but make sure you turn off safe boot at startup before rebooting. with the restart press F2 to enter bios and try switching to ahci then restart.

Most of the Dell laptop systems will set the SATA controller to RAID so as to configure the M.2 slot as SATA so it can use the Intel SATA/PCIe Premium driver on a NVMe drive.

So you probably need to leave it as RAID and especially if you are using Intel's Optane Memory.

Welcome to the Dell Community @caboy 

What OS's are you trying to dual boot???

Best regards,

U2

I was planning Windows 10 and Linux.  Right now Linux cannot see the drive.  I believe this is due to the RAID mode being on.

@caboy 

On most systems that support Linux:

Dell will include it under "Operating System" on the driver support page.

Yours only has:

Windows 10 64-bit

Windows 11

https://www.dell.com/support/home/en-us/product-support/product/xps-13-9305-laptop/drivers

Your XPS 13 9305 supports these operating systems:

https://www.dell.com/support/home/en-us/drivers/supportedos/xps-13-9305-laptop?ref=oscompatibility

Note regarding operating systems not listed above:

Dell may not support an operating system for various reasons, including discontinued support from the software vendor, lack of availability with certain products, or other reasons.

Best regards,

U2

@caboy Do you have an Intel Optane storage device installed?  If so, the system has to be in RAID mode for that to work properly.  Otherwise, the behavior you're reporting is certainly strange.  I would suggest using the Reset to Factory Defaults option in the BIOS/UEFI Setup interface, applying settings, restarting, and then seeing if that changes anything.  If not, try flashing the firmware either in an OS if you've got one you can use or using the BIOS Flash Utility that you can access from the F12 one-time boot menu.  You'll need to copy the Windows-based BIOS updater file onto a FAT32-formatted flash drive in order to allow that firmware flash utility to perform the flash.  Then see if you can change to AHCI and have the setting persist.

Hi, We haven’t heard from you. You could get back to us with an update when you’re ready, and one of our experts will assist you further.

-Regards,

Paventhan M

I was not able to figure out if it has an Optaine Storage device or not.  

Something weird I noticed.  The selector has 3 options: Storage Disabled, AHCI, and RAID.  As an experiment I set it to "disabled".  After clicking "apply" it still seemed to be set to "RAID".  I rebooted.  The boot process complained it could not find a storage device.  - I will try this again to confirm I remember this correctly. 

Fedora is able to boot and see the drives.  My previous tests were with CentOS 7.  Which cannot see the drives.

I will need to test further to see if it is in AHCI mode or not.  

Hi There, We see that you had contacted us recently regarding issues with your computer, and our experts & community users have been waiting for your confirmation on the outcome of the suggested steps/ provide the requested details, this service ticket is currently in-progress. Please reply to this message, so we can keep you posted with further updates on the service status.

Linux shows that there are no AHCI devices available "dmesg | grep -i ahci". It does show RAID devices "dmesg | grep -i raid".

The developer version of the XPS 13 allows the AHCI setting to be set in the UEFI.

Why did Dell disable that in this version of the laptop?

Is there a way to re-enable it?

Why would Dell intentionally cripple the UEFI?

We haven't heard back from you in a while. If you do need additional help, please don't hesitate to contact us back. Thank you.

Following up on this.  I upgraded the ssd to a bigger drive.  I was then able to switch the setting.  It looks like the included drive could only support RAID mode.  The new drive, oddly enough, only supports AHCI mode.