Having an issue with my display and trying to determine if the RTX2080 is the culprit or if it's Windows 10 or Nvidia contrtol panel.
 
This is a new system I've built and I have been using a standard 24" monitor which has been fine. When I try and hook up my Sony 55" XBR 4K TV via HDMI and boot up, it defaults to 1080p. I am able to change the resolution in both Windows and the Nvidia control panel and everything looks fine until I reboot. Then the screen becomes green pink and gray. If I launch Nvidia control panel to change the resolution, the green/pink/gray vanishes and the screen looks normal again. I previously had a GTX1080 on my old system hooked up to this Sony TV with no issues and prefer 3840x2160 which worked great. If I try and change the resolution to that setting via either nvidia control panel or windows display settings it looks fine - until I reboot and then it boots back up to green/pink/gray. Note: I have 2 other 24" monitors hooked up to the RTX2080 and they both are at 1920x1080 and are not affected by any of these changes. Only the Sony isn't cooperating. Oddly though, if I set the system to show 1920x1080, the machine will reboot just fine with no issues but that resolution is too large for me. Also, if I set the resolution to 4096x2160 it will also reboot with no issues - the problem with this resolution is that the desktop extends beyond the screen cutting off the left and right sides. I've attempted to manually resize the 4096x2160 screen in the Nvidia control panel to shrink the width and have been successful - until I reboot. Then it's back to green/pink/gray. Any time it boots with this issue, I can change the resolution to anything and when I hit "apply" the green/pink/gray go right back to normal - until I reboot.
 
So since the Sony worked perfectly before with Windows 10 using the GTX1080, I think I can eliminate the TV as the culprit. I've reinstalled the latest Nvidia drivers 2X with the same result. So is this a function of the RTX2080, an issue with Windows 10 or something with the Nvidia drivers?
 
ASUS ROG Maximus XI Extreme
i9-9900KS @ 4GHz (native)
RTX2080
32GB G Skill RAM
EVGA 1300 G2 power supply
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It definitely does this. Also, when it boots up green/pink/gray if I leave it on the login screen long enough to where it goes to sleep, as soon as I wake it up, it's back to normal and I can log in with no issues. One other thing, if I log in with it green/pink/gray and take a screenshot, the colors are normal, not green/pink/gray.
 
Soooo confirming your hypothesis, is this an EVGA, Windows or NVidia issue? 

I actually did all the above with no luck. Then I went into the TVs settings and found something for "Enhanced Format" for HDMI so I turned it on an low and behold the problem is fixed! Don't understand why my previous GTX1080 on this same TV didn't have issues but as long as it's working then I'm happy!
 
Thanks to all who gave suggestions!