--- dust and fingerprints will appear sometimes, consider yourself warned ---
Here's her last build state. An i5 12600KF and 32GB RAM aboard an ASRock Z690M-ITX/ax, crammed under a Noctua NH-D15S (that I've had for years) that barely clears the surrounding components. There's a 1TB TEAM GROUP MP34 and 2TB SK Hynix P41 SSD under there too. The GPU behind the DIY ducting - thanks Lego Technic box for the nice thing cardboard - is an Intel ARC A770 LE. It's all powered by an EVGA 850W GM (an SFX PSU). There's an LG WH14NS40 up top for ripping CDs, DVDs, and up to 4K BluRays. And 2 1TB MX500s behind the front panel.
I have torn her down for a rebuild. I want to build more ducting to direct airflow better.
The GPU puts out 200W of heat into the very small bottom area of the case, and the PSU tends to suck that hot air up, increasing the temp it runs at. I want to box in the GPU entirely, forcing it to intake from the bottom of the case (old ducting accomplishes this) and forcing it to exhaust out the side panel fan (new ducting needed).
I've also rotated the cooler 90 degrees, in order to exhaust straight out the back of the case. I'm going to fit some 40mm fans in between the CPU cooler and the optical drive in order to pull fresh air down from the top of the case. I may box in the PSU exhaust as well, to ensure it vents out the side case and no hot air leaks into the CPU cooler area. I'll try and fit a fan at the bottom to pull fresh air into the PSU area, and the CPU cooler will also pull a bit from there as well.
Small update, I've ordered a Sapphire Pulse 9060 XT 16GB, to replace the ARC A770. ARC A-series really suffers on Linux, and I don't think I'll ever return to Windows again given Microsoft is doubling, tripling, and quadrupling down on bullshit. AMD GPUs are first class experiences on Linux according to my friends who have been using them for years, so hopefully things will "Just Work" now.
The new GPU arrived:
I got it installed:
And ducting made from another Lego box to keep it from ingesting its own exhaust, and force the side fan to pull out said exhaust:
I didn't get photos, but I also installed two 40mm fans in between the CPU cooler and the ODD to pull fresh air in from the top. And I added a 60mm fan at the bottom of the case, near the GPU, to pull fresh air in to the PSU area, and the CPU cooler also intakes from there. Temps remain nice and low (50s-70s GPU, 30s-70s CPU, it'll barely touch 80C sometimes), so nothing's eating hot air from any other component.