B1g B1ll

Looking to upgrade my son's pc
Current spec
Asus H81m plus mb
I5 4430 cpu
Xfx r9 280x double disapation black edition gpu
8gb XMS3 Corsair 2 x 8g ddr3 ram
Msi Dragon liquid cooler
In an Aerocool X predator gaming cube
Any suggestions either keeping with the mb and there fore the cpu socket
Or changing board and cpu to 1151 socket what if anything would be cross compatable
Or do I sell the existing pc and add money to upgrade
Any help much appreciated