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.
| NOTE: | If the monitor goes blank for while, but then comes back, the computer is attempting to change the display resolution or other display setting. A blank screen and quiet clicking noises can be normal while the monitor makes the changes to the display. If the monitor stays blank for more than 5 seconds and then reverts back to the same display settings (no change is noticeable), then the monitor was not able to enter into the new display settings. When this happens, you must adjust the display settings in the software program that was being used to change the display setting. For example, when starting a game from the in-game menu, the video display goes blank for while, but then goes back to a menu or back to the Windows desktop. to fix, adjust the display resolution for the game (from the game's option menu) to match the Windows desktop display resolution. |
Before you begin
Check the following items before using the steps in this document:
If you have a flat panel LCD monitor, unplug the monitor power cable, wait about 30 seconds, reconnect the cable and then turn on the monitor. This resets the electronics on the monitor.
Make sure the monitor has power - the light on the monitor is on. If the light on the monitor is off, the monitor does not have power. Connect it to a different power outlet.
If the monitor has a detachable video cable, obtain a second monitor cable for testing purposes in case the cable is bad.
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 computer from starting.
Update the BIOS
to resolve this issue.
Step 1: Connect the computer to another monitor
Connect another monitor to the computer to determine which device has the problem (the monitor or the computer). This step is very important
to help you determine if the problem is coming from the computer or the monitor. If necessary, temporarily connect the computer to a friends monitor for troubleshooting purposes.
After the monitor is connected, turn on the computer and the monitor. What happens?
Step 2: Is the video connection damaged?
Inspect the video cable and video connectors for damage. Check for sharp bends or breaks in the cable and bent or broken pins at the connectors. With the monitor and computer 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 computer and monitor. If the display is still blank, continue to the next step.
Step 3: Resetting and updating the BIOS
You can use these steps even though you will not be able to see anything on the monitor.
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 repeatedly press one of the following keyboard keys. Press the key about once every second for 5 seconds after turning the computer on.
For HP and Compaq computers that came with Windows 7 and Vista, press F10
.
For HP and Compaq computers that came with Windows XP, press F1
.
For Compaq Presario desktop computers built prior to 2002, press F10
.
Wait another 5 seconds.
Press the F5
key. This restores the default settings of the BIOS.
Press the Enter
key. This accepts the changes.
Press the F10
key. This saves the changes.
Press the Enter
key. This saves the changes and exits from the BIOS.
If a BIOS update was not available or the monitor is still blank, continue to the next step.
Step 4: Reseating loose internal components
If the computer case was recently serviced or moved, a card, cable, memory module, or processor may have become loose. When this happens, the computer 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 can be damaged by electrostatic discharge (ESD). To reduce the chance of ESD damage, work over a noncarpeted floor, use a static dissipative work surface (such as a conductive foam pad), and wear an ESD wrist strap connected to a grounded surface. |
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 computer for 5 seconds.
Remove the screw(s) that retain the panel or cover from the rear of the computer.
Slide the side panel off from the rear of the computer.
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 computer cables, and turn on the computer 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 5: Changing the display resolution
This step will not work if you cannot view the first startup screens as noted in the previous section.
Use the following steps to change to a compatible display resolution and color depth setting from a standard graphics mode. For flat panel LCD monitors, set the display resolution to the monitor's native display resolution.
| NOTE: | If you cannot select your monitor's native display resolution, then update the computer's video drivers and repeat this step. |
Turn on the computer and press the F8
key repeatedly when the first startup screen appears.
Change the display resolution from low resolution environment as follows.
Step 6: 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 computer), press the power button briefly or press the Suspend key on the keyboard to see if the computer comes out of a suspended state. If the computer opens into a suspended state every time the computer is started, use the following steps to disable Power Savings in the BIOS:
Turn on the computer and repeatedly press one of the following keyboard keys. Press the key about once every second for 5 seconds after turning the computer on.
For HP and Compaq computers that came with Windows 7 and Vista, press F10
.
For HP and Compaq computers that came with Windows XP, press F1
.
For Compaq Presario desktop computers built prior to 2002, press F10
.
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 computer 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.
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 computer (if the monitor works on another computer) or a defective monitor (the monitor does not work on another computer). The defective hardware should be replaced or serviced.
