I have a server which has 2 CPU Sockets and I used only one of the sockets so far. I have VMware ESXi V.6.0.0 installed and running. I know that the free version supports 2 physical CPU, so in order to upgrade my physical machine, do I have to buy the exact same CPU again, or can I buy a newer/better/different CPU? I understand that I won't be able to create a machine using parts of both CPU's later on, but if I create only 2 VM's running both on one physical core, will this be possible?
do I have to buy the exact same CPU again?
If you want to run both the existing CPU and the new one then they have to be the exact same CPU.
or can I buy a newer/better/different CPU?
You can put in a newer one if you pull out the old one.