The HP PC has been plugged in but turned off for about a year. My wife used it to watch youtube cooking videos in the den. She is a great cook by the way. It's a HP Pavilion Slim line s3521p PC. AMD Athlon X2 4096mb 500g HD with a onboard video by Nvidia GeForce 6150se Graphics. Originally Vista, but updated to W10 about three years ago. Turned it on to get W10 updates, but the monitor is blank. I changed monitors and also blank. Ordered another video pci-e graphics card and installed it, monitor still dead. I get no signal from the new vga port on the new card and no signal from the onboard vga port. Any ideas on how to force the pc to use the new vga port with out a working monitor plugged in?