I just bought a new computer- less than a week out of the box. It has worked fine until now, but this morning my husband told me he had been using a flash drive to move some files onto the new computer. He left for awhile and the then came back to find the monitor screen had gone haywire- it was full of what I can best describe as the 'snow' you might see on an old TV, but it was more like green plaid snow. I turned the computer off, waited a moment then turned it back on. The monitor did not turn on and reboot with the system, so I turned it on manually. First the power button when to green, but it almost immediately went to yellow with the screen black. I cannot get it out of what I understand is power save mode as it continually goes back to yellow. When I press any of the screen keys on the monitor I see a message. "1. Analog input in power save mode. Press computer power button or any key on keyboard or move mouse."
Trying any of this does not change a thing.
Can anyone tell me what is wrong?

Please help.

I didn't find the right solution from the Internet.

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