Are their any guides or documentation on how to performance tune our server? (PDM Pro 2016). What about hardware sizing guidelines?

When our system was setup in 2017 we had less than a dozen users. We know regularly run over 60 consecutive users and are experiencing general performance problems like long check-ins/outs/ general lag, and occasional access timeouts/denials.

Not sure if their are any Windows or program settings we can change, or if SQL things like number of DB connections and cache sizes can be improved.