what should I upgrade first
current build
cpu i5 3570k 3,8ghz
mobo msi z77-g43
ram 16gb corsair vengeance lp 1600mhz
gpu xfx 7870 black
psu corsair cx750m
want to upgrade to http://uk.pcpartpicker.com/p/GHnjzy
gpu either evga gtx 970 sc acx 2.0 water cooled or gigabyte r9 390 g1 watercooled
hoping to go black and white theme