For real? I have Dell XPS at work an had tons of problems installing linux on it. I ended up finding a respined Ubuntu ISO in github that has plenty of patches pre-applied that mostly works, but still have some issues now and then with random freezes and with a thunderbolt dock. Admittedly, I was not a desktop linux user and didn't have much experience tinkering with it, but a coworker of mine who has been using linux for many years and who I would consider a fairly advanced user (heavily configured distro using his own modified tiled desktop environment, etc) had the same issues and couldn't even figured out how to install Debian on it without having the fans spin up randomly and with everything working (I think the webcam didn't work).

Try updating the firmware of the laptop and possibly the dock. Then do a clean install of Ubuntu. I just upgraded my stock 18.04 with stock 19.04, everything works great.

Now that I think of it, you can boot with the LiveCD to see if it will help before trying this.

If the random freezes continue you may have bad ram or other components need to be replaced.