I wanted something small, quiet and powerful for gaming and Hyper-V so opted for an i9-9900k, 32GB RAM and an RTX 2080 in a NZXT H200 case.
I would've preferred to go down the AMD route but Microsoft still haven't enabled nested virtualisation in Windows 10 for Ryzen.
I replaced the two stock case fans with Noctua NF-S12A fans as the chassis fan header on the motherboard ran the stock fan at full speed which was noisy as hell.
CPU Idle: 27c
GPU Idle: 28c
Case Temp: 35c
Edit: I think I screwed the GPU in slightly too high as the ports on the back weren't level. Dropped it a few mm and added another picture of the GPU from a different angle.
Edit: Two more pictures added. One with the GPU stand that came with the case and another with a piece of lego propping up the card. Thanks for the suggestions smithd4 and JoeyDelgadoJK.