Is there an easy way to tell? It displays dots and red, green, and blue scrambled colors when the computer is booting up and this should be out of the resolution of the monitor. I used to see the screen collapse when I pulled the plug, and I could hear a high pitch whistle when it booted up. None of that happens anymore. I had been trying to get my computer to work with it and I am wondering if I somehow damaged it. It had been working fine when thte Tekken Tag board was in there, but I can not check to see if it still works with the board because I sold it. I had started to think I would just put in a spare 27 inch TV and take out the monitor, but I do not even have a way to do this right now since my video card doesn't have TV out.
Update: I remembered that a few weeks ago when I was trying to figure this out, I saw a spark from the plug that connects the monitor to the power supply. I realized that the previous owner had just pushed the wires into the plastic piece and taped it. I went to check that connection and I blew a fuse, so now the marquee doesn't even light up anymore. Is it possible that the spark I saw last week blew out the monitor? I do not know how this stuff works. Obviously I need to get a new fuse.