I am building a computer for my friend. It is a strictly gaming/interneting computer. The main games he want/needs to computer to perform for is Guild Wars 2, wants to be able to play on ultra in 1080p and Civ 5. Hes not really into to FPS currently so this doesn't have to play Metro LL or BF4, mostly MMO/RTS games.
His other concerns are he wants good airflow so that things stay cool. wants reliable PSU. And wants a stable GPU.