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rezarishehri Author

Level 1

4 points

Macbook Pro / External Display Flicker - glitches

Hi , i have MacBook Pro (Retina, 13-inch, Early 2015) , i was using an external display with no problems until this morning like everyday i turned on my Macbook and Viewsonic Monitor which is connected to my Mac with HDMI cable , but when the computer booted my external display starts flickering and glitching(have stable whitenoise - moving whitenoise - color distortion - contrast distortion) and every 2,3 seconds it turned completly black like its off and then showed glitches again for 2,3 seconds , and after around 3,4 times it completly goes black , i tested these :

-changing HDMI cable

-changing monitor's power cable

-testing cables and monitor with other devices like TV , and PC and they were fine

-i did reset NVRAM / PRAM

-i did reset SMC

-i adjust and tried every possible display setting

-i updated my OS to macOS Catalina version 10.15.7 (19H15)