I have an older desktop, high-end custom-built,win 10, all up to date, used infrequently. Today when powered up none of the 3 main peripherals work...vga monitor, usb mouse and keyboard. monitor: no signal. no lights on mouse or keyboard. Any ideas?
Is the motherboard light on? Power supply fan running? CPU fan running? If so, I would start by unplugging from the power source, then remove and reseat all components.