So after many hours of working (8 hours), I finally got home to try out Forza 7 on my new One X. After playing it, I felt underwhelmed a bit; I couldn't put my finger on what the issue was, but I knew the settings were off. So in the setup area I found that the 4K and HDR was not coming through for some reason, but my new receiver had the 4K passthrough.
What was wrong?
From 11 PM to 3 PM i was flipping HDMI cords around and messing with settings on both my TV and Xbox, I finally realized that my receiver didn't automatically have the 4K passthrough on. Why it didn't occur to me to check the middle man was dumb on my end because I should have known better, but if anyone has the same issue that may be the solution.
Now I have to go to work, again, and think about playing some 4K games...