Cpu for 4k gaming?

[Some1helpme]

Wondering what cpu to get for 4k gaming. Got me a good priced 1080ti but my aged i5 4690k only runs it to 80 ish %. Thinking about getting an i7 8700. This is what i got so far.

https://ibb.co/iQHOYe

Going to reuse case, hhd and ssd.

 

[edo101]

Going to do a bit of research on that, would be cheaper then a (almost) full new system. This was on assassins creed origins. Only thing I had running beside game was msi after burner to get the ingame stats. Plus what ever windows needs in background. Like to keep unneeded processes off even if I'm on something simple as gmail. Going to try fc5 and see how much the CPU is at there

Did you ever decide? I have an i7 930 at 4Ghz I've been holding onto because of the ridiculous prices of newer build.
I also game at 4K and 4K3D 3dTV and sometimes at 1440p for RTS games on my monitor

AC Origins also gives me the same stuff. For me CPU usage will go to 80% and GPU sometimes will dip as low as 60%. I wish There were reviews that compare processors at higher resolutions. instead they always stop at 1080p. Its so asinine. Some of us want to know how much we are losing at 1440p and 4K for older cpus