the best case for small pc right now is the r200 case. a good 650w power supply will work fine in your rig. if your going to run it 24/7 bit mining spend the extra money on a 750w gold unit. http://pcpartpicker.com/part/corsair-power-supply-cs750m
with haswell mb and cpu make sure your power supply is haswell tested. if not you can have issues do to haswell low power.