Why do you want to change the port? It will be much better to have a strong password and to install scripts for protecting the server as BFD (BruteForce Detection) and Dos-Evasive (Denial Of Service).
The Brute Force Detection script should be set to block anyIP that makes some number (by example 5) failed log-ins within some time (by example 1 minute).
Thanks HostingAspNet for your suggestions.
Actually this will be the second windows server and the first one is being attacked literally every second with a RDP login attempt.
I already have Syspeace running on that other server to block any IP that makes more then 10 attempts in 10 minutes.
And I also use a minimum 16 character random strong password with all kinds of character types.
Are the above methods sufficient in your opinion? Would it not help to change the rdp port, add a rule to the firewall for the new port number so my network bandwidth(however small) is not wasted on these clowns?