Macbook randomly shutdown 4k external monitor I have a Macbook 16inch connecting to Dell 24inch 4k P2415Q with Moshi USB-C to Mini DisplayPort, bought from Apple.
After 1-2 hours the monitor just shut down like there's no signal, macbook still running. I have to turn off and turn on the monitor to reconnect but it keeps happening all day.
I've done these things so far:

Open / Close lid while connecting to the monitor. 
Switch between ports. 
Reset NVRAM, PRAM, SMC. 
Tested with Macbook 13 (2016), same problem
Tested with my gaming desktop, same monitor same cable, working well, no issue.

Has anyone experienced same issue before ?
Turn out the problem is the the monitor. I've bought a new one and it's ok now.
Still don't know why it only happened to Macbooks not windows