With 3 770s you are officially in overkill land...what resolution are you gaming at?
If you're at 1080p then 2 770s are overkill let alone 3...
At 1080p even single screen 2 GTX 770's are definetly not overkill. Im running 2 780 Ti's on a single 1080p and its far from overkill to make sure minimum framerates never drop below 40-50fps.......... There are games ou there that will give a pair of 770's a serious workout and have minimum fps BELOW 30fps..........my old 780's in sli couldn't fully max out certain games even.