My webserver is a VM and currently running 2 cores which are Intel Xeon e7-8837 @ 2.67Ghz, with 4GB ram and a 200gb HDD. This machine sits between 186 to 268 MHz usage most of the time. It is running out intranet, two osTicket installations , a Drupal Site, 7 Wordpress Sites, numerous custom PHP scripts, and two other web sites. The osTicket sites have about 10k and 1500 tickets.We have not had any performance complaints.