cards that are connected with extenders are terrible for gaming. My evaluation of your rig was on a pure mining basis. . You could always stick with 1 or 2 cards (connected via x16) while you game, and connect the rest of the cards using extenders. it's highly unlikely that you will use ALL of your card's processing power, but you'll save a ton of money.

extenders can be obtained here:
https://forum.bitcoin.org/index.php?topic=6128.0 (already pre-cut for x16 cards)
or ebay (not pre-cut, but only $4 vs $16)