Would it be worth it to buy used CPU cooler from my friend for $30? He has had it for about 2 months. I would either look to replace my graphics card cooling with it or replace my Hyper 212. Thanks.
As long as it's working, $30 isn't a bad price. It probably won't make too much of a difference for your cpu since the Hyper 212 is a pretty good air cooler. I would recommend using it for your gpu.