External Management of Power and RESet Switches of PC/Server via RPi.GPIO and a raspberry pi as the controller.
Send the command via ssh or set up a web server that executes the script.
The python script works in combination with the additional circuit that you can either have printed, make your own, or use the schematic to build on a breadboard.
You can retrieve those files either from the schematics folder or from my easyeda project page: https://easyeda.com/vandabbin/empress
I know I haven't been very descriptive on how to use or set any of this up. Sorry. When I have time I will try and put more details here.