When I'm rendering a video or playing a game consuming a little bit more cpu it tarts a beep sound, but don't lag or crash. Where does the sound come and how can I disable this?
If it is not coming from your normal speakers it may be the internal speaker and you are hearing some sort of alarm. For instance if a processor is over heating or a fan not spinning. I would look into that.
If it is an alarm from the bios you can turn them off usually in the bios. However that can be dangerous if a real issue arrises. Something is likely triggering this, as you already know, what is doing it is the question.