Why is the video output on the video card not working?

Question

Video cards

Given:
two monitors, video card palit gtx 1060 6gb dual (with 3 DP and 1 HDMI outputs). One monitor is connected via HDMI-HDMI, the second one is connected via DisplayPort-DisplayPort.

Everything worked fine, but at one moment it stopped, the image disappeared on both monitors. I tried to reconnect the wires, checked everything, nothing changed. I switched the monitor from DisplayPort to another DisplayPort output of the video card - it worked. The monitor connected via HDMI refuses to show the image. But, in the meantime, I can move the mouse cursor behind the working monitor to the second one and it is displayed in the nvidia control panel: I


examined the video card and contacts, apparently everything is ok with it. I connected a non-working monitor to another computer - it works on it. Latest video card drivers.

That is, apparently, the two ports to which the monitors were previously connected died (but not completely)? How can this be diagnosed, understood what is the cause and, if possible, corrected independently?