How did you switch them into 444 mode?
EDIT: Nevermind, I'm an idiot. I was thinking you did something else.
Yeah it's just UHD Deep Color on the LG TV. The Yamaha receiver was a little tougher to switch but not overly difficult. Needed to hold some buttons for advanced setup on power up and switch to 4k mode 1.
Also, I noticed Nex Machina has HDR support on PC and it's very nice. Colors really pop now since it uses a lot of neon.