Dual Monitor causes Blackscreen and system freezes

[DarkusCanning]

Launching the game on my System, where I have dual Monitors connected, one 1440p and one FullHD Vertical, I get a black screen on Monitor 2 and the game on Monitor 1. Now what happens is simple, I see my RGB Lighting effects slow down to a crawl, same Issue as if my CPU was pegged 100%.

The Game itself runs at around 15FPS at all times and it's quite difficult to operate the Menu at this level. This issue was nowhere to be found and quite frankly, I wouldn't have figured it out, unless I tried page 4 of google Results where someone had the same Issue with Dirt 4 of all games. Turning off the second Monitor completly via Windows (not just turning it off via the Button and active Signal) let's the Game run at full speed, between 50 - 70FPS.

Alas I have no Idea why this would be happening, just that it's reproducable.

Specs:
AMD Ryzen 3700X at Stock cooled with Corsair AIO 150i Pro
32GB Corsair Vengeance PRO (4*8gb) at 3200 Speeds
Gigabyte X570 Aorus Master Mainboard
Gigabyte 2080TI Non XTreme Edition
Corsair Commander Pro with 4 LL120 RGB Fans and 4 LED Strips inside case.
Z35P GSYNC Monitor at 3440x1440x100hz (connected via DP)
Dell 27" Potrait at 1080x1920x60hz (connected via DP)