John wants to become a Minecraft developer. He has a MacMini, and it's laggy. So he needs to look at getting a windows based machine for a server. Leo uses a Linux Box running Debian. Leo says you may not have to use another computer. Leo says to look in the settings and see if you can optimize it. You may have to run it from the command line, but it should be plenty powerful and fast to run Minecraft. Check out your memory switches in the start command. Under the command line, you start it with -x ms. There are two different memory settings running SPIGOT.
Hell, you can use a Raspberry Pi. Check out your plugins as well. They can kill you. But if you want to get a dedicated server, Leo advises a NUC. Run Linux on it and it'll be lean and mean. Also, port forward to a dedicated port and turn on the white list feature if you're going public with it.