With an unlocked CPU Throttlestop 8.60 software allows control of Voltage and multiplier in Windows. I don't know which specific families of CPUs it supports. Also OEM motherboards often have CPU wattage limits that keep Extreme series CPUs from running.
If you go to userbenchmark.com and look for your system you can see if any K series CPUs are running. But it doesn't distinguish between tower. desktop, and SFF versions of the same system which may differ.
http://www.userbenchmark.com/?redirFrom=userbenchmark.com&
Here's a thread about this.
https://www.techpowerup.com/forums/threads/throttlestop-overclocking-desktop-pcs.235975/
OEM computers may have limited power from the VRM on the MB so the overclock can vary quite a bit...