Problem with the monitor
The three boxes represent the built-in diagnostics of the monitor. The letters G is green, B is blue and R is for red, the 3 color guns of the picture tube of your monitor. The words "Self Test" indicates that it is in diagnostic mode since it has powered up, it is also then expecting a video signal from a source to be coming in; the display "Check Your PC And Signal Cable" indicates that it is not receiving any video signal from the source which is your PC or more specifically the PC's video card; and the display "Monitor Working" indicates that the diagnostic has determined that nothing is wrong with itself and therefore it has got to be your PC that is in question. The intermittent appearance of the boxes is when the diagnostics restarts itself and eventually finds the same problem.
To determine if it is the PC or the monitor, use another PC (even a laptop with matching VGA output) and try it with your Compaq monitor, see it it will work or alternately, try a different monitor to connect to your PC. The outcome will determine which is at fault.
If you have determined/verified that it is indeed the PC, you should focus on the video/graphics card. In some PC models/versions, the graphics/video is built-in to the motherboard and you should check the memory since this is shared. The only way is to replace either.
Hope that this be of some help/idea. Pls post back how things worked out or should you need additional information.
Good luck and kind regards.
Dec 07, 2007 |
Compaq FS7550 17" CRT Monitor