I needed to replace an aging Dell XPS 13 with the latest XPS 13 9310 Developer Edition that comes preinstalled with Ubuntu 20.04 LTS, but unfortunately it wasn't for sale in the Nordic countries.
So having to install Ubuntu myself, I decided to go with the much cheaper XPS 13 9305, but with a spec similar to what I would have picked for the 9310.
The most significant hardware difference between the two is the screen. The 9305 has a FHD 3-sided InfinityEdge screen with a bezel at the bottom, whereas the 9310 has a 4-sided InfinityEdge screen with options ranging from FHD+ to UHD+.
On the up-side the 9305 has 3 USB-C ports, two of which have Thunderbolt 4 support. The 9310 only has two.
The XPS 13 9305 isn't officially Ubuntu Desktop Certified Hardware at the time of writing, but here's the spoiler.. Everything just works with the standard Ubuntu Desktop 20.04.2 LTS. Trackpad, WiFi, Bluetooth, Thunderbolt, speakers, mic, cam etc.
This is courtesy of Ubuntu 20.04.2's Hardware Enablement (HWE) that backports the newer Linux kernel 5.8.0 with the latest drivers and graphics support from Ubuntu 20.10 to Ubuntu 20.04.2 LTS.
Part of the sexiness of an XPS 13 ultrabook is the small form factor and light weight that allows me to throw it in backpack and bring it on my motorcycle to wherever I need to go to. But the compromise is that it only has a few ports.
This is overcome by using a Dell WD19TBS Thunderbolt Dock. Instead of having cables and dongles hanging off the ultrabook, the clutter is hidden behind the dock. Combined with the heavy duty Dell MDA20 dual monitor arm it really frees up the desk. When I need to bring the ultrabook somewhere else I only have to unplug one cable.
I use the dock in a multi monitor setup. The primary monitor is a Dell 27" 4K P2717Q connected to the dock's Thunderbolt 3 port and the secondary monitor is an older Dell 24" QHD S2417DG connected to the HDMI port.
And btw. connecting one of the 9305's Thunderbolt 4 ports directly to the 4K monitor works too.
Download the Ubuntu 20.04.2.0 LTS desktop image and write it to an USB-C stick with the StartUp Disk Creator application ("sudo apt install usb-creator-gtk" if it isn't already installed).
Connect the USB-C stick to the 9305 and press F12 to enter the BIOS while it's booting. Open the Boot Configuration and add the image on the USB-C stick as a boot option. Move the option to the top of the list, apply the change and exit.
From there on it's the standard Ubuntu installation process. You don't have to do anything special to get the 5.8.0 kernel. You are done when the installation is over. There is no Thunderbolt or dock specific setup either, just plug stuff in.