Everquest is an old game folks and by default it only runs on 1 core.
To fix this you must set what is called CPU Affinity.
- In windows 10, right click your EQ Icon on the desktop.
- Select Open File Location
- In the search box on the right type eqclient.ini
- Double click the eqclient.ini file, it should open in notepad.
- Press Control + F
- type CPU and hit find Next
- You will see CPUAffinity1=1
- Change the last 1 to -1
- Hit Find Next
- If you run more than 1 eq instance ( ie box) you will see CPUAffinity2=2
- Change the last 2 to -1
- Repeat these steps for as many it finds changing the last number to -1
- Hit Control + S when your done and close the file.
- This will allow each instance to use all the cores of your processor!