Mac hardware for 4k/uhd?

server-mac

#1

I've been using a mac mini as Plex Server for a few years now and I tried to play back some UHD/4k releases but had constant stutter/lag.

So, my question, will a new mac mini manage playback 4k/uhd material?

Current specs:
Mini 2012
2,5Ghz i5,
8GB
Intel HD Graphic 4000
SSD

New specs for mini:
1,4Ghz i5 (whaaa?) OR 2,6Ghz i5
8GB
Intel HD Graphic 5000 OR Intel Iris Graphics (is any of them enough for 4k?)
SSD

If none of them is enough, what alternatives do I have in the pc-world? I need a machine that does not make any noise more or less, just like a mini.