Has anyone added an ssd to an XPS8910 desktop?

I can confirm that a XPS 8910 will boot from an SSD. There is a problem, apparently, with using Samsung M.2 drives in an XPS 8920.

The general process is to backup your data to a USB or external drive and be sure you have the current Windows 10 install files on another USB (download from Microsoft). Then shut down the system and unplug the computer, disconnect the SATA cable from the hard disk and install the SSD. You can get a M.2 drive that installs on the motherboard or a SSD card that attaches to a SATA connection. Then put the USB drive holding the WIndows 10 OS into a free USB slot. Restart the system and start pressing F12 until a boot menu comes up. Choose to boot from the USB drive which will install  to the SSD. You should let the system reboot from the SSD by removing the USB drive. Then power down the system, reattach the SATA cable to the hard disk. Put the cover on and reboot. If all goes as expected, the system should boot from the SSD and you can use the hard disk for data. Restore from the backup.

I did not mention that after the OS is installed you need to be sure that the Dell drivers are installed--go to the Dell support site and search for the drivers that need to be installed.

I installed an Samsung 850 EVO 2.5" 500GB SSD in my XPS 8910. You will need an SATA III cable and a 2.5" to 3.5" bay mounting bracket to mount the SSD in the empty hard drive cage. The steps are installed the SSD, use the Samsung Data Migration software to clone the existing hard drive, disconnect the hard drive when the cloning is complete, and then boot the system. Once everything is working you can re-initialize the hard drive (using Disk Management) to use as a data disk; just be sure that you are booting from the SSD. Cloning does not require installing Windows and device drivers.

Note that SATA Operation mode is probably set to RAID in the BIOS. To change switch Windows 10 from RAID to AHCI operation within Windows 10 without having to reinstall:

1. Right-click the Windows Start Menu. Choose Command Prompt (Admin).

2. Type this command and press ENTER: bcdedit /set {current} safeboot minimal

3. Restart the computer and enter BIOS Setup (the key to press varies between systems).

4. Change the SATA Operation mode to AHCI from either IDE or RAID (again, the language varies).

5. Save changes and exit Setup and Windows will automatically boot to Safe Mode.

6. Right-click the Windows Start Menu once more. Choose Command Prompt (Admin).

7. Type this command and press ENTER: bcdedit /deletevalue {current} safeboot

8. Reboot once more and Windows will automatically start with AHCI drivers enabled.

Samsung Magician software requires AHCI mode to work probably.

it's not a difficult task for AOMEI Backupper. this software can only clone OS to SSD hard drive(https://www.backup-utility.com/clone/clone-dell-hard-drive-to-ssd-3889i.html )and contain all things concerned to  boot your computer.