I wrote this back in 2022 when I worked there, and it's still fundamentally relevant today: https://news.ycombinator.com/item?id=30678324

They are selling you a rack of computers instead of a single computer, with well integrated high speed connection, storage, power, and cooling.

I think this blog covers it pretty well:

https://oxide.computer/blog/the-cloud-computer

Basically they sell a pre-assembled rack of compute, storage and networking with their own open source management software to build on-premise clouds.

Server racks which are vertically integrated and provide great cooling, are quiet, and fully vertically integrated software (including bootloaders, hypervisor, etc. -- no BIOS!).

This includes everything from the rack itself to the PDU/switch/BMC, to the actual server blade and its chassis.

All presented in a nice package to give you a on-prem cloud-like experience.

Looks like a mainframe computer and their selling point is that the operating system is open source.

I have no idea why you'd buy that over any of the more established players that have a proven track record of being able to support these multi-million dollar machines for many years.