It's hard to figure out what you're saying. Are you saying that when you disconnected the graphics cable from the monitor, and then ran the test, that you did see the image with the red, green, and blue squares?
If the monitor test showed the red, green, and blue squares then there is a problem with the cable, graphics card, or the motherboard itself. Do you have a different cable you can test with?
If you get no signal to the monitor with a different cable, then you'll know that it may be either the graphics card or the motherboard that has a problem. If you don't have a different cable to test with, try disconnecting the cable from the graphics card and then connect it to the onboard graphics port instead. If you get a good signal to the monitor using the onboard graphics port, then the graphics card is most likely the problem.
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