Wednesday, September 12, 2007

Problem Solving - The Computer Monitor Is Blank

Problem: When turn on computer and the monitor remains blank, although the monitor's power light is on.

Possible Causes: You have a hardware problem or a BIOS setup problem. Your computer hardware has not been installed correctly, your motherboard's jumpers are set incorrectly, your BIOS settings are not correct, or your computer or peripherals have been shorted out and/or have some other mechanical problem.

What to try.

1. Check and make sure all cables are firmly attached to the back of the computer and to all external devices. Retry.

2. Remove the case cover from the computer. Make sure all cables (hard drive, power cables, other disk cables) inside the computer are firmly attached. Press down on all ISA and PCI cards and make sure they are firmly seated. Make sure your DRAM memory cards are firmly seated. Feel the top of the CPU and make sure it is not hot (warm is OK). Retry.

3. This step is only for newly built computers that have not successfully booted. Get out your motherboard manual, or download one from the manufacturer's site, and go over all your motherboard jumper settings. Set the jumpers in the most conservative position. Review all your accessory wire connections (keyboard lock, hard drive access light, etc.) and make sure the connectors to the motherboard are facing the same direction. Retry.

4. Turn the computer back on with the case off. Verify that your CPU and power supply fan are running. If either one is not running you have a problem. If the power supply fan is not running replace the power supply (make sure the power connectors are correctly attached to the motherboard). Make sure the CPU fan is connected to power on the motherboard. If it is correctly connected and still doesn't run, replace it. Retry.

5. Unplug your computer. Remove all PCI and ISA cards. Reinstall the video card and disconnect the hard drive cable. Plug in the keyboard, video cable, and power cable. Restart your computer. If this worked, go to Step 6. If your DOS screen doesn't come up at this point try the following ideas.

a. Closely examine your motherboard and make sure it is not making contact with the computer case, which will short it.
b. Your video card, video cable, or monitor may be malfunctioning. Borrow a video card, cable and monitor, retry.
c. Remove and reinstall your DRAM. If your computer can not find system memory it will not POST.
d. Remove the CPU and reinstall it.
e. Follow your motherboard manual's instructions for resetting your BIOS to its default configuration.

If your computer still will not boot into a DOS screen, seek professional help.

6. If you now have a DOS screen on your monitor, attach your hard drive cable and reboot. Make sure the hard drive is correctly set up in the BIOS. Press the Delete key during the POST memory check to enter the BIOS. If your hard drive doesn't work, you have incorrectly attached the drive ribbon cable or power cable.

7. Add your other PCI and ISA cards back into the computer one at a time. Reboot after each card is installed to make sure the new card isn't causing a problem.