Monitor is Blank after Starting the Computer

HP and Compaq Desktop PCs - Monitor is Blank after Starting the Computer
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This document pertains to HP and Compaq computers.

A monitor is connected to the computer and has power but does not display anything. Use the steps in this document to resolve this issue or to determine if the monitor is defective.

Before you begin
Check the following items before using the steps in this document:


If the monitor has a detachable cable, obtain a second monitor cable for testing purposes in case the cable is bad.

Make sure the monitor has power - the light on the monitor is on. If the light is off, the monitor does not have power or is not working.

Disconnect all connected devices except the mouse, keyboard and monitor. This includes thumb drives and camera-type memory cards from card reader slots.

With the devices disconnected, restart the computer. If the computer starts and the monitor now displays a picture, a device is preventing the PC from starting. Update the BIOS to resolve this issue.


Step 1: Connect the monitor to a different computer
If possible, connect the monitor to another computer that is known to work correctly. Connecting the monitor to a different computer helps determine if the problem is with the monitor or with the video display hardware (the video card).


If another computer is not available, continue at Step 2: Connecting the computer to a different monitor .


If the monitor displays correctly, then reconnect the monitor to the original PC and continue at Step 4: Resetting and updating the BIOS .


If the monitor does not display anything when connected to another PC, there is a problem with the monitor or its cables. Try the following:


Unplug the monitor power cable, wait about 30 seconds and then try again.

The video cable may be damaged. Replace it with another video cable and try again. If the video cable is permanently attached to the monitor, the monitor may have to be replaced or serviced.

The monitor power cable may be damaged. Use a different power cable to test the monitor.

If the monitor does not work after testing the cables, the the monitor may have to be replaced or serviced.


Step 2: Connect the computer to a another monitor
Try connecting another monitor to the computer. Connecting a different monitor helps determine if the problem is with the monitor or with the video display hardware (the video card).

If another monitor is not available, continue at Step 3: Is a video connector damaged?

If you can connect a different monitor, perform the following steps depending on how the monitor behaves:


If the monitor does not display anything, continue at Step 3: Is the video connection damaged?

If the monitor displays the first startup screen(s) but then goes black, there is a problem with Windows starting. Skip to step 6 to continue troubleshooting the problem.

If the new monitor works fine and Windows opens, either the original connection or the original monitor is faulty. Continue to the next step to check the video connection.


Step 3: Is the video connection damaged?
Check the monitor video cable connector for damage. Check for bent or broken pins. With the monitor and PC off, try to straighten bent pins with a small metal tube, like the tip of an empty mechanical pencil or the tip of a retracted pen.


Figure 1: Video connector



If you had to straighten any pins, reconnect the monitor making sure that the video cable is firmly connected and then turn on the PC and monitor. If the display is still blank, continue to the next step.

Step 4: Resetting and updating the BIOS
In case an item was changed in the BIOS, such as the primary display device setting, use the following steps to reset the BIOS back to its default configuration:


Turn on the computer and press the keyboard key that enters the BIOS Setup screen key when the keyboard light comes on. The key to enter the BIOS should be one of the following:


HP and Compaq desktop computers that came with Windows Vista, press F10.

For HP Pavilions desktop computers that came with Windows XP or previous versions of Windows, press F1.

Compaq Presario desktop computers built after 2002, press F1.

Compaq Presario desktop computers built prior to 2002, press F10.


Wait 5 seconds.

Press the F5 key to restore the default settings of the BIOS.

Press Enter to accept the change and wait five seconds.

Press the F10 and then the Enter key to save the changes and exit from the BIOS.

The monitor should now display the first screens received from the computer (the logo screens). If not, find and download the latest BIOS update if one is available for your computer.

If a BIOS update was not available or the monitor is still blank, continue to the next step.


Step 5: Reseating loose internal components
If the PC case was recently serviced or moved, a card, cable, memory module, or processor may have become loose. When this happens, the PC might make a beeping sound when turned on. Use the following steps to check for loose components:



WARNING: The edges of metal panels can cut skin. Be careful not to slide skin along any interior metal edge of the computer.



CAUTION: This product contains components that are easily damaged by electrostatic discharge (ESD). To reduce the chance of ESD damage, work over a non-carpeted floor, use a static dissipative work surface (like a conductive foam pad), and wear an ESD wrist strap that is connected to a grounded surface, like the metal frame of a computer.


Unplug all cables except for the power. Write down each cable location if you do not already know where it connects.

With the power cable removed press the Power button on the front of the PC for 5 seconds.

Remove the screw(s) that retain the panel or cover from the rear of the PC.



Slide the side panel off from the rear of the PC.




Gently press down on the outside edges of cards and memory modules that are inserted into the motherboard to better seat them. Do not press too hard.

Gently press down on the connectors of the flat ribbon cables to seat them.

Replace the side panel and screw(s), reconnect the PC cables, and turn on the PC on.

If the monitor still displays a black screen, the video hardware may be faulty and needs to be replaced or serviced. If the monitor displays the first startup screen but does not display Windows, continue to the next step.


Step 6: Changing the display resolution
Use the following steps to change to a compatible display resolution and color depth setting from a standard graphics mode:



NOTE: If the monitor is an LCD Flat Panel monitor, use the following steps to set the PC to the monitors native resolution. Changing the display setting to the native resolution of the monitor ensures compatibility and the best possible display quality.


Turn on the PC and press the F8 key repeatedly when the first startup screen appears.

If you are using Windows Vista, select Enable low resolution video, press Enter, and wait until Windows opens. To set display settings that match the monitor, use the steps in the HP support document, Changing Display Settings, Background Image, and Screen Saver in Windows Vista .

If you are using Windows XP, select Enable VGA Mode, press Enter, and wait until Windows opens. Continue using these steps to set display resolution.

If you are using Windows 98 or ME, select Safe Mode and perform the following steps to enter into a standard VGA mode:

Once Windows opens to the desktop in Safe Mode, click Start, and Run.

In the Open field type msconfig and press Enter.

The MS Configuration Utility window appears.

Click the Advanced button, and select VGA 640 x 480 x 16 if it is available.

Click OK and restart the computer.

After Windows opens, click Start, and Run.

In the Open field type msconfig and press Enter.

Click the Advanced button, and remove the checkmark next to VGA 640 x 480 x 16.

Click OK. Do NOT restart the computer.

After Windows opens, right click on an open area of the desktop and select Properties.

In the Display Properties window, click the Settings tab.

Adjust the Colors (Win98/Me) or Color quality (WinXP) and Screen area (Win98/Me) or Screen resolution (WinXP) settings. A screen resolution of 1024x768 and a color quality of True Color (Win98/Me) or Highest (WinXP) is recommended.

Click Apply after you have made your adjustment.

The screen should blank out temporarily and come back.

If you are happy with the new display settings, click Yes on the Monitor Settings windows. If you are not happy or if the screen just goes black, wait and Windows sets the screen back to the way it was before. Try another setting until you find a display configuration that's compatible with the monitor and meets your needs.



NOTE: If the monitor is an LCD flat panel, and the native resolution is not available, download and install an updated video driver software for your PC. Updating the video driver software can add more resolutions (graphics modes). For more information about how to download software from HP, refer to the HP support document Obtaining Software and Drivers .


Step 7: Disabling power settings in BIOS
If Windows was recently upgraded, Windows might be starting up into a Power Saving state and producing the blank screen before it loads. After Windows loads (about 2 minutes after turning on the PC), press the power button briefly or press the Suspend key on the keyboard to see if the PC comes out of a suspended state. If the PC opens into a suspended state every time the PC is started, use the following steps to disable Power Savings in the BIOS:


Turn on the computer and press the F1 key repeatedly when the first screen appears until Entering Setup ... displays.

In the Setup screen, press the Right Arrow key and select Power.

Press the Down Arrow key to select and configure one of the following items depending on what appears on your screen:


Power Savings, APM, or Advanced Power Management - select Disabled and press the F10 key to save the settings and Exit.

APIC Interrupt Routing - If the PC is using Windows XP and this setting is disabled, select enabled and press F10 to save the settings and exit. Let Windows restart and set your power preferences from within Windows.

If Windows still does not appear or you are unable to use the power options in Windows, find and download the latest BIOS update if one is available for your computer.

Reset the APIC Interrupt back to its previous setting if problems occur.



If changing the power setting does not work, this issue is probably caused by faulty hardware - either the video hardware on the PC (if the monitor works on another PC) or a defective monitor (the monitor does not work on another PC). The defective hardware should be replaced or serviced.