Make sure power button (or switch) is ON.

       Make sure A/C power cord is securely connected to the DC power supply and the power supply is firmly connected to the Display

      Make sure the video cable supplied with the Display is tightly secured to the video output port on the back of computer. If the other end of the video cable is not attached permanently to the Display, tightly secure it to the Display.

       Adjust brightness and contrast.

       If any colors (red, green, or blue) are missing, check the video cable to make sure it is securely connected. Losses or broken pins in the cable connector could cause an improper connection.

      Press only one button at a time.

       Make sure the video input signals are within the monitor's specified frequency range.

       Try the monitor with another power source and/or computer system.

       Make sure the video cable supplied with the Display is tightly secured to the video output port on the back of computer.

      Make sure your graphics card is set to non-interlaced mode.

      The Display was pre-adjusted in the factory with standard VGA timing. Due to output timing differences among various VGA cards, you may initially experience an unstable and/or unclear display when a new display mode or new VGA card is selected.

      You need to adjust the On Screen Display (OSD) Settings on the LCD. Refer to your Manual to learn more about the specific functions of your model. Common problems are horizontal or vertical black borders.

      •  To stabilize, adjust the monitor's “Frequency/Clock” setting

      •  To clarify, press “Auto Adjust” button from the display.

      •  If you use extension cable to connect your LCD monitors to your PC system, please check your extension cable or connect your LCD monitors directly to your PC system.

 
     You will see this on an otherwise blank screen. Assuming that the data cable is plugged in correctly, the video card is feeding the monitor a signal stream in excess of what the monitor can accommodate. The two main causes for this are that the user has set either the resolution or the vertical frequency rate too high. For example, you might set a new graphics card to display at 1280 x 1024, but if the monitor is only capable of 1024 x 768 resolution, you'll get a Sync Out of Range error.

        Because you obviously can't make settings changes from within regular Windows, you'll need to reboot into Windows Safe Mode. When you restart the system, there is a point during boot up when the system switches from reporting diagnostics and detected components to loading Windows. This point is usually accompanied by a beep and the screen going black. Just before this point, you want to start repeatedly hitting the F8 key. This should bring up a menu of Windows boot options. The one you want to pick is Safe Mode.

     From Safe Mode, right-click the Desktop and select Properties. Go to the Settings tab and use the slider to drop your resolution a notch or two. Reboot and let Windows try to go into Normal mode. If this still doesn't work, go back into Safe Mode and get to the Settings tab of Display Properties. Click the Advanced button, go to the Monitor tab, and check your refresh rate. The lowest advisable rate is usually 60Hz, although this works better for LCD (liquid-crystal display) screens than CRTs (cathode ray tubes). Apply the change and reboot.

      You may be running the screen at a resolution that is too low. Look in the user manual for your monitors' particular setting.

      This usually happens the first time the monitor is plugged in or the when the mains (electrical outlet) has been switched off and on.

      Switching off the monitor using the power button on the monitor then switching it on again will solve the problem. It is recommended to switch off the monitor using the power button rather than switching it off from the mains.

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