Negative delta time!
History: UGameEngine::Tick <- UpdateWorld <- MainLoop

Program to set afinyty for use only 1 core

Download this tool

Click on browse , go to l2 folder
then pick 1 core and click on Lauch like in the picture.

Task manager

1 open L2
2 Open task manager , pick l2 process and 2º click (the right)

3 slect only 1 core

You should do this fast.. is better option 1.

AMD CPU Driver Fix:
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