I have a feeling he is cpu bottlenecked.
My 8600k hits in the 60s at some points in the game (possibly higher in fights but I dont look at OSD in fights), if I took away 2 cores that 60 becomes 80, take away 800mhz for ivy bridge clocks, than that 80 becomes 93, then takeaway IPC improvements and you see the problem.
Thats not even taking into account dropping down from ddr4 to ddr3 as well.
This indicates about a 90% all core benefit on my cpu vs his.
https://cpu.userbenchmark.com/Compare/Intel-Core-i5-8600K-vs-Intel-Core-i5-3570K/3941vs1316
I didnt install anything special but had perf mon running on my other screen to take a look. According to that my cpu is always at 100 and my gpu at 10%...Doesnt matter if i have my video settings at ultra or on medium the fps is the same. Surely my ivybridge isnt killing performance that badly?