How to host large server with 60+ players without lags?

How does big servers (DarkRP) hosting 60+ players without lags?

A good host?
I wrote up a good list here
http://forum.facepunch.com/showthread.php?t=1502705&p=49594028#post49594028

What server specs does the server need to host a gmod darkrp server with a lot of addons and up to 60 players without lag?

A 4790k cpu. Rest doesnt really matter.

And anything else? Like Tickrate or something like that?

or something additional?

Probably should use around 20 tickrate.

Okay thanks. Should i change anything with the sv_minrate and
sv_maxrate? Or just leave them?