20 pin vs 19 pin displayport cable

Hey folks. I've been doing some research for a friend who wanted to build his own PC and while researching for monitors, I wanted to look up for an issue that I had.

My monitor is PG248Q and my GPU is a Gigabyte 1080. I am using the DP cable that came with the monitor. My monitor sometimes flickers or it is more like it blacks out. They are not long and I don't think it goes to sleep or turns off and on again.

Now I'm scared that this cable is going to damage my GPU. I don't really know if this 20th pin is sending power as well, but I am just afraid. Does anyone have any information on this?

Thanks.