Selfhosted

Look for a processor for the same socket that supports more RAM and make sure the Motherboard can handle it - maybe you're lucky and it's not a limit of that architecture.

If that won't work, breakup your self-hosting needs into multiple machines and add another second hand or cheap machine to the pile.

I've worked in designing computer systems to handle tons of data and requests and often the only reasonable solution is to break up the load and throw more machines at it (for example, when serving millions of requests on a website, just put a load balancer in front of it that assigns user sessions and associated requests to multiple machines, so the load balancer pretty much just routes request by user session whilst the heavy processing stuff is done by multiple machines in such a way the you can just expand the whole thing by adding more machines).

In a self-hosting scenario I suspect you'll have a lot of margin for expansion by splitting services into multiple hosts and using stuff like network shared drives in the background for shared data, before you have to fully upgrade a host machine because you hit that architecture's maximum memory.

Granted, if a single service whose load can't be broken down so that you can run it as a cluster, needs more memory than you can put in any of your machines, then you're stuck having to get a new machine, but even then by splitting services you can get a machine with a newer architecture that can handle more memory but is still cheap (such as a cheap mini-PC) and just move that memory-heavy service to it whilst leaving CPU intensive services in the old but more powerful machine.