I'd like a desktop optimized for streaming games to other devices in the house! (plus serves docker and AI services)

My current setup revolves around having a central PC that other devices (Meta Quest 3, Steam Deck, iPad, Mac Mini, Nvidia Shield, etc.) all connect to and stream games from, usually through Moonlight/Sunshine or with Virtual Desktop on Quest. I've got most key devices wired to 1GB switches and have access points running wifi 6 so I'm confident in my backend.

My current machine however is... old. It's a MSI laptop from 2016 or so and it has a gtx 1070. The lid broke off years ago, the fans have been replaced 3x, and things are really getting sluggish even with low settings in modern games. It's time for an upgrade.

I also have a QNAP NAS that is not only acting as storage for the entire network but also runs 30+ docker containers for services like Home Assistant, Nextcloud, and other similar services. Not only that, but it also hosts a virtual windows machine that's used by someone in the house for work which must be up all the time (it runs one database-ish windows-only app). I would like to migrate these services

Finally, my M2 Mac Mini is currently the designated AI machine but it's not meant for this use case. Ideally I would like to unload local AI/LLM responsibilities onto a more powerful and 'dedicated' machine. It's unlikely that AI services will be used while gaming.

So I want to build one super-machine that will take full responsibility for being the back-end.

Things I am considering:

- Should it be a VM host and I create specific VMs for each purpose (gaming, AI, etc.)?
- (Where) can I use Linux over Windows (ie do I play a lot of windows-only games that don't work under proton? Maybe like gta? idk)
- Do I need more than one graphics card or is a single powerful one fine?

The machine will be stored in a closet so case/lights aren't a thought/should be basic but the closet gets hot in the summer so good cooling will be necessary especially with such a heavy workload. Being able to rack mount it in the future would be neat but not at all required. My switches are all 1GB now but I could add a 2.5GB NIC to the QNAP NAS for a direct connection if it was worth it. I'd also ideally want to future proof the machine for when I upgrade switches later.

Thanks for anyone who takes the time to read through this and make suggestions!