I have 2 l3+, set with hiveos at 504mh/s they absorb 660w, at the socket they will be 10% more or so.
Fans with ambient temperatures between 15 and 20 degrees c are always between 30 and 50%, rarely more.
yeah that's about right.
and if he backs them down just a bit. say 450mhs and 600 watts he can set fans lower.