Packard-Bell PC stoped starting up…

It doesn’t have video…NO POST…but it starts the drives. It worked perfectly just the other day. I removed all cards and memory and still got no beep codes. It’s power supply is running, but it isn’t even getting to a screen. HELP! It belongs to a friend, and now it doesn’t work. I feel responsible. What could be happening?

Sincerely,

Troubled Technician