I hope I'm not in the wrong community but I really wanted to get some opinions on that.
In short, it may be a it of an unpopular opinion, but I really hate the gaming aesthetics with all the RGB lights and glass and in general how modern 3rd party PC cases look like. On the other hand I really enjoy the look of a most of the recent Lenovo ThinkCentres and ThinkStations as well as Fujitsu's Esprimos. There is just something about this industrial matte black with red accents I can't resist.
What I would love to do is to take some cheap Lenovo Thinkcentre, slap a GPU in it and have a budget Linux gaming PC, but the problem is most of the parts in these office systems are proprietary. It seems that I can't easily upgrade the PSU to handle a proper GPU, nor can I swap the motherboard for a new one if I wanted to.
Does anyone have any idea on which models of ThinkCentres/Stations are easily upgradeable or of any cases that have this understated industrial office look to them? The only case I kinda like is the Fractal North, but I get really discouraged when I compare their prices to a fully equipped Lenovo office PC and it just doesn't look as good.
Also, I've looked into Lenovo Legion and HP Omen prebuilts, and while they're not as bad a 3rd party cases, I just don't like them as much as say a P520, which unfortunately comes with some awful proprietary motherboard supporting only Xeons from 2017.
Anyway, I'm sorry for the rant. I'd love to hear your opinions and suggestions.
I somehow missed you mentioning Fractal. My point still stands though. I've got the original Define XL. it's more than a decade old and has housed either one or 3 computers of Theseus, depending. So a pretty good ROI based on its lifespan.
It's not exactly what you're looking for but Fractal makes some solid, plain black cases. Most of their models can come with or without windows. The Define line is my favorite - they're very quiet, spacious, and pretty well designed.
https://www.fractal-design.com/products/cases/define/