I have a MacBook Pro (13-inch, 2017, Two Thunderbolt 3 ports) version 10.14.5.

A first monitor (DELL P2719HC) is connected through thunderbolt 3 while a second monitor (DELL E2313H) is connected through a VGA adapter. The latter is the one flickering!

Flickering stops when I disconnect the first monitor. Thus, it's not a problem of the adapter, nor the screen. I am guessing this is due to my laptop not being able to give enough fps to both screens (they both require a 60Hz refresh rate at minimum, which I cannot change event with some command line tools).

I tried to reset VRAM and SMC, but it did not work.

What else can I do?


This problem is not due to the computer not being able to serve the necessary amount of "fps". Instead this is a hardware problem.

VGA is an analog signal. If the signal is distorted or interfered with, it could problems such as flickering. The flickering stops when you disconnect the first monitor - which indicates that this monitor (and cable) is the source of interference.

I would suggest replacing the VGA cable with one with a ferrite bead instead. Another option is to replace the VGA adapter with a DVI adapter and connect to the monitor using a DVI cable.

If possible you could also try to the cables seperate from each other physically (i.e. get distance between them) - but it is difficult as they need to plug in to the computer very near each other.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .