Hi Alex, maybe check the advanced properties of the "High performance" power plan. Maybe it still has some CPU throttling set on it. If not I guess it is just getting too hot with all CPU cores running and throttling anyway. I'll make a setting in the next v4 beta where you can limit the number of CPU cores used for file loading maybe using just 2 or 3 cores on that particular machine will work better if it just can't thermally handle all at once.

- Michael