she is challenging you to a scream contest. scream louder and prove dominance.
I have proven that never works
Tell her to calm down
Also that never works
Hate to say it but its kinda a vague story, personally it sounds like its a "loss of control" thing, because you are moving things over, maybe she wasnt as concerned about the PS4 because its like 1 thing that is used just for fun, But a PC is both entertainment and essential to life (school, work, ect.)