i undervolted my 7700k and my 1080 mini very slightly, and they hold steady Overclocked while undervolted slightly, which helps slightly with temps at idle and load.
with my HDPLEX-300 and Dell 330 I'm well within power limits, never had a hard shutdown.
So you can max an S4 mini, but if you really wanna max it then go for the thicker front panel, 1080 Ti Mini, HDPLEX-400 and a custom
@guryhwa Power Brick... its a small increase in cost for the HDPLEX-400, so you could just go for a Gury PSU & power brick combo. :/