Display Duplication Causes Stuttering

[Allo]

About 8 months ago I started streaming in a dual pc setup and picked up a Asus Strix 2070 Super for my main PC, and whenever the second PC is on and my main PC is duplicating the display to the capture card it causes stutters like the following: https://clips.twitch.tv/AmericanCarelessCormorantBCWarrior

This issue happens only when the second PC is on and the main PC is duplicating the display. My display is a 144hz running on Display Port while the capture card is 144hz over HDMI (brand new 2.0 cable). It happens no matter what program is up, even on desktop so it isn't just an issue with CSGO.

Main PC:

• 8700k overclocked to 4.8Ghz (using the mobo built in tool)
• 32gb 3200hz CL16 TridentZ
• Asus Strix 2070 Super
• Asus ROG Strix Z370-E Gaming BIOS 1802
• Samsung 970 Pro 500gb
• BenQ xl2411p

Stream PC(parts less important since this pc works fine):

• 9700k overclocked to 4.5Ghz (using the mobo built in tool)
• 16gb 3200hz
• nvidia 1070
• Elgato 4k60pro mk2

 

Things I've tried:

• updating all drivers
• uninstalling with ddu and reinstalling nvidia driver
• disabling overclocks
• going through the event log to try and fix any errors or warnings
• new htmi cables on both hdmi ports