Your son is already at the highest CPU the R7 supports as the 8700k and 8086k are effectively the same
I've read some of the older posts but I'm just decently tech savvy so based on the below current specs, what's the best CPU I can upgrade to do without having to do something highly technical/expert level? Thanks Intel Core i7 8086K (6-Core/12-Thread, 12MB Cache, up to 5GHz w/ Intel Turbo Boost Technology) 300 Series Chipset Family LPV Controller (Z370) - A2C9 Bios Version/Date:  Alienware 1.0.16, 8/28/2018 Baseboard Product: 0VDT73 Baseboard Version: A00 Video Card:  NVIDIA GeForce GTX 1080 Ti with 11GB GDDR5X
What Can I Upgrade my son's R7 CPU to?