I can't get my Dell monitor to boot up. I got this computer and monitor from my grandparents, they had it set up just fine at their house, just got a new one. The monitor and HP computer are connected via VGA cable, but when I start the computer, the monitor just says "Entering power saving mode". I don't know where my problem lies or how to go about fixing it, seeing as I only have the one monitor that won't display.