First time build

no need to buy thermal paste, 212 evo comes with high quality paste inside the package

and to avoid conflict with 212 evo, ram should be low profile heatsink
http://pcpartpicker.com/part/corsair-memory-cmx8gx3m2b1600c9

for that spec, i wouldnt put cx series. use TX series instead that has much better quaality
http://pcpartpicker.com/part/corsair-power-supply-cmpsu750txv2

for mouse, i will keep the same brand with keyboard
http://pcpartpicker.com/part/corsair-mouse-ch9000002na

just my 2 cents :)