Tutorial: Ubuntu 18.04 / RTX 2080 / Razer Core v1  

Hi there,

I had a bit of hassle setting up my new RTX 2080 (Gigabyte RTX 2080 OC 8G) eGPU on Ubuntu 18.04 using a Razer Core v1.
So I thought I would share how I did it!

The problem: I had a working setup with the same hardware but a different GPU (Gigabyte 1060 GTX OC 6G).
When I switched the GPU, I was not able to boot on Windows or Linux: after selecting the OS in grub, the screen switched to
black and nothing happened.

1. In my BIOS (XPS 13 9380), I disabled the "Thunderbolt Boot Support". After that, Windows booted ok. But in Ubuntu,
   the NVIDIA drivers would not load and I had a strange error in dmesg:

   NVRM: BAR1 is 0M @ 0x0

2. I removed all the nvidia related packages:
   

   sudo apt-get --purge remove 'nvidia*'

3. Reboot.
4. Add the following kernel parameters in /etc/default/grub:
   

   pcie_ports=native pci=assign-busses,nocrs,realloc iommu=on

5. Update grub:
   

   sudo update-grub

6. Reboot.
7. Install the 440 NVIDIA drivers:
   

   sudo apt-get install nvidia-driver-440

8. Reboot.
9. At this point, the NVIDIA GPU was recognized and listed in nvidia-smi. But I was stuck in a login loop, presumably because the X server settings were incorrect.
   So I installed egpu-switcher:

   sudo add-apt-repository ppa:hertg/egpu-switcher
   sudo apt update
   sudo apt install egpu-switcher
   sudo egpu-switcher setup

10. Reboot.
11. Everything works as expected!

I hope it can help others!