i7's that have Iris are
5950HQ
5850HQ
5750HQ
5755C
5775R
i5's that have Iris are
5675C
5675R
5575R
There are a bunch of Skylake processors with them: https://en.wikipedia.org/wiki/Skylake_(microarchitecture)#Mainstream_and_high-end_desktop_processors
Along with Haswell: https://en.wikipedia.org/wiki/Haswell_(microarchitecture)#Desktop_processors
Additionally some of the Xeon E3 V4 processors have it: https://www.anandtech.com/show/9532/the-intel-broadwell-xeon-e3-v4-review-95w-65w-35w-1285-1285l-1265
I couldn't find any CPU that would work on an ATX mother board, am I mistaken?
Yeah you are mistaken. There are plenty aval that will work on any Z97 or H97 mobo provided the BIOS is up to date and supports those CPU's per manufacturer.
If one had like 50 Z97/H97 mobos, they could make a killing. Unfortunately you need mobo, ram, HDD/flash drive and PSU. But I can still stomp that $250 Brix deal into the dust with what ive found.
What did you find that beats the Brix deal? I cant find one that's anywhere close to 249.