I am not well informed about EPYC CPUs, and server workstation related stuffs.
I am looking to purchase a workstation/ server with dual EPYC 9654 cpus on a Gigabyte MZ73-LM1, however with budget constraints would like to consider getting only one cpu and dropping in another one later down the line.
I am aware of the potential lost of ram slots and pcie connections due to the lack of the second cpu on a dual cpu motherboard.
I am just curious whether future drop ins are possible with minimal drawbacks or instability.
So I haven’t done this on a newer platform, but I was running a dual socket Opteron 4000 board for years with a single CPU. Finally started running into RAM limitations and opted to spend maybe $20 on a second CPU and $100 on a PILE of DDR3, and now that system’s good for another few years.
All this to say: yes the ability to double the capacity of a server overnight has its advantages, so long as you spec it correctly.
Mine was a file server… mileage was a lot shorter for a similar VM server, but the Opterons were terrible. I imagine Epyc will age much better.
Most EPYC CPU are locked to the motherboard they are installed to once the system is first turned on? So if you plan on buying a used EPYC you buy one already installed on a motherboard. Also EPYC’s like to have a lot of air being bown across them. They are not ment to be installed in a regular case. You want to install them in an server case and them rack the case. Also they are loud I mean Jet engine loud. You don’t want to be in the same room with them, not without ear protection. I am planing to get a EPYC , when I have saved enough money. What you might to look at instead is a used Theedripper depending on what you are going to use it for.
Lenovo, Dell and HP motherboards vendor-lock EPYC CPUs at boot, other motherboards do not.
Rack-mount any CPU are loud simply because they can have fast fans at the expense of reduced heatsink surface area, because they’re designed to go in a data center.
You can certainly use a big cooler and put them in a “normal” case, since EPYCs have similar maximum TDP as the turbo power usage of recent desktop CPUs like the i9 14th gen. Actually they are easier to cool than smaller sockets because the package surface area is larger and thus the thermal density is lower.
I do not have any experience with EPYC; I only repeated what I heard to @Onthefence. According to @xzpfzxds, only Lenovo, Dell, and HP motherboard vendors lock EPYC CPUs at boot.