Having 100% Cpu usage on loading screens but only 40% max on any thing else? with a low of 25%. XD this is a bug

this makes no sense. what is going on here? why is the game doing this? is it downloading something? is it the anti cheat software. this is just crazy. the game is almost unplayable at times. even the story mode has this insane 90%-100% cpu usage. some times alt tabbing works.