Custom Resolution Utility (CRU)

[Mussels]

This one might be a simple answer of "monitor can't do it" but i've been working on why my displays can't OC higher, and discovered a few things

* Gsync off can reach 70Hz
* Gsync on can do 65Hz, but only with a 64 FPS cap or i get horizontal black lines across the exact center of the display
* Some combinations allow 10 bit colour while others don't - is there any way to know what the limit is there? Does it just need X bandwidth spare?
* It's not a pixel clock bandwidth limit, as i can raise various settings upto 600MHz without problem - as low as 550 has issues at 66Hz for example
*Both displays are 32" 4K 60Hz VA panels, one Kogan one LG. Both seem to use the same panel as they behave exactly the same in all things, other than different stock profile settings. (Like Gsync H-Rate being 135-135 on LG but 160-160 on Kogan)

So to the actual questions:

1. Is there any recommended settings to adjust like the horizontal rate in the Gsync/Vsync settings? - i've seen no guides mention this, other than one standalone post from ToastyX to state keeping it at a static value

2. Is that tearing me putting the wrong porch/sync width settings in, or is that just the limit of the display? I've tried the different preset profiles and some random adjustments, but no luck improving that.

Tearing example:
https://imgur.com/a/A3oD2Px (it moves up and down depending on screen content/brightness)

Edit: Okay this ones dumb yet weird. It was Fast vsync being enabled, despite the game being DX12 causing the flicker. I reset all monitor settings to default and the problem still existed, leading to finding out that fast vsync was the issue somehow. Go figure?