Please check to see if there is a light on the monitor
Press a space bar or move the mouse to wake-up the PC. sometime it goes to sleep. wait one minutes or so to see if it comes up.
If there is no light try to pull the black power cable on the back of the monitor and plug it back in. The power cable does not have any screws attached.
If there is an orange light then check the computer to see if there is any light on the front of the computer.
If there is a green light then check to see if the cable from the monitor is connected properly.
There are only two cables on the back of the monitor. One is the power and the other is the VGA, HDMI, DP or DVI that goes to the back of the computer.
If all cable is connected properly then pull the power cable on the back of the computer. The power cables look like the same as the monitor power cable. You need to wait at least 60 second for the main board power to go down.
Plug the power cable back in and turn on. Check to see if there is any light or hear anything at all. If it is quiet and does not work
then please download the remote support software by click this LINK TO DOWNLOAD REMOTE SUPPORT SOFTWARE. After download Click open to install then click confirm. Let me know what is the Computer Name