Most motherboards these days support higher density RAM so can support 128GB like this one. Likely 32GB per slot (4 slots). My server based board can go to 512GB but I only run 64GB for my use cases. But, you can run Unraid on an old computer easily.

a.co/d/hk2la3S This is the chassis I have. And 2 32GB sticks. MB has room for 4 so I could go up to 128

What's the upside to this over a Tower? Better cooling since it's on a lot?

Usually configured to handle more drives than a tower can. I have a ThinkServer that can be stood up or laid down but can only hold 8 drives. Also you can rack mount them with other rack mount gear like networking gear, etc.

Gotcha.

Yeah this thing can hold 15 HDDs + 4 NVME drives on the Mobo. And yeah it's rackmounted in the basement with all the network stuff in a rolling rack.

My wife would kill me if I did a setup like that. I might be able to do a small server for security, videos/media/photos and our electronic documents. Already have a gaming PC so I already have most of what I want.

Nice part of UnRaid is that it works off a USB drive. So if you find a cheap PC that has a QuickSync enabled Intel chipset (for transcoding videos), you can add any drive sizes you like (parity has to be equal or larger than the largest data drive). I have about 48TB.

I run my cameras, home assistant, media server, documents, occasional VM, Tailscale, personal computer local backups, etc.

My old gaming PC has an AMD chip so, based on your above reply, I am not sure I could use it. Not terribly old, I just wanted to upgrade to DDR5 when I got a new graphics card.

You still can. It's usually easier to offload transcoding of video to a CPU. Just pop your old GPU in! I have a Quadro P400 I picked up for like $80 off eBay. The Intel thing is mostly around if you had one, it likely has QuickSync built in.

Offload to a GPU*

I need to look into tailscale. I have connectivity for things (like audiobookshelf) done via cloudflare tunnels.

Does make it a bit less complicated. Great when you are on the road and want access as well to your network.

I actually bought a adapter so I could plug the USB for Unraid directly into one of the free USB headers on the mobile. Mostly cause I foresaw kids potentially yanking the drive out of a port.