More than year and not fixed yet so this is my last try before i send this GPU to grave.
I have two monitor: Odyssey G7 ( 2560 x 1440p 240Hz 8 Bit) and C27HG70 ( 2560 x 1440p 144Hz 10 Bit)
As you can see below, once i plug two monitors VRAM read go above the limit
Which cause this (Same effects when you kill your GPU with too much O.C)
This only happen when i open images or using browser and even right now while i am typing in this forum, the funny thing once i open any game VRAM Clock speed drop to 1000 MHz stable without fluctuation and everything works fine for hours but once i close the game and in light usage my screen start again to show wired lines only in main monitor.
I tried to plug old LCD 1920x1080 60 Hz with 2560x1440 1440p 144Hz and same problem appeared again
I tried to lower resolution on second monitor from 144Hz to 60 Hz in windwos settings but within seconds i get blue screen with error code THREAD_STUCK_IN_DEVICE_DRIVER
and sometimes error code VIDEO_TDR_FAILURE
This problem since the release date of radeon VII i tried all drivers months by months but nothing fixed my issue and reported many times in AMD Report tool but i think they simply don't care.
Last thing the almighty black screen is 10x times worst when i plug two monitors in Adrenalin 2020 Edition 20.9.1 or any old driver, for now i am using 20.Q3.1 Enterprise driver because i did not get any black screen yet in 20.Q3.1 driver.
Using Radeon VII since lunch date and i was living inside black screen simulator unable to record unable to use blender in multi monitors, my experience with AMD for more than year was really bad it is like having a prototype GPU and you are forced to live with all bugs for ever.