Forget trying to find one with 4k pass through, for it will be too "new" if it does and will NOT have 7.1 inputs for analog from your pc. As mentioned get one that is HDMI with 1080P for stuff that still outputs in 1080P, and anything 4K run directly to your tv using it as the HDMI/DP 4K switch, and run a SPDIF to the new receiver if it has smart stuff on it so it will pass the DD or DTS signal from like Hulu, or netflix, or XXXX to the receiver. Then use 3.5mm to rca cables to go from your sound card to the analog inputs of the receiver. This way for all 4k your using your tv as if it is a $k HDMI switch, and like my PS3 and Xbox 360 go to my receiver, then out it to my tv and it decodes its digital sound, and since its doesnt do 4k, pumping its 1080P to the tv, lessens the need for a receiver with a bunch of older hdmi inputs for I have but the 2 consoles through hDMI, and then my Shield and PC goes right to the TV and out the spdif to the receiver for the all important sound decoding if in live, or my pc's analog so that the games play in 5.1/7.1 if no option, and I dont want it in stereo playing off the spdif connection, and its just a matter of selecting EXT inputs on the receiver using an assignable different input to switch over too.
I know sounds crazy, but its really easy, just again dont waste ur money on a 4k pass through one, for look in the back of it on google images and see that it will have 7.1 out, but it will not have 7.1 in anymore, hence y u need an older unit to do it for they had that back in the day, and why they got rid of it is beyond me, for every since Logitech put to rest the Z5500's, there really isnt a good powerful alternative I can ever find, and I like my stuff loud and proud.