I recently got a new gaming pc. I built it and it was tested out in the shop and it worked. I then flew it home and got a new monitor with it. However, when I try to turn it on, it doesn't. It just says "Analog" in the top left hand corner or "HDMI" if I'm using an hdmi cable. I was told that I needed to plug it into the graphics card instead of the motherboard. Is this true? And can you please suggest any other reason that my computer won't turn on. Thanks!