Desktop - No POST / No Video

Use this checklist if video is not displayed when computer starts, or the Power On Self Test (POST) fails.

POST refers to activity occurring immediately after turning on the computer, and prior to an operating system starting. During POST, the computer is preparing to initiate operating system startup.

Typical Symptoms

  • Beep Codes
  • POST error messages
  • No video on the display

Notes

Make sure computer has power

To check computer for power, make sure at least one of the following occurs:

  • Computer and power supply fans start up
  • Beeps and other computer sounds are audible
  • Front panel LEDs light up

Note: When checking for computer activity, ignore monitor LEDs, startup menus, and messages.

If there is no evidence of power, go to the My desktop does not power on checklist.

Drain stored power and then restart the computer

  1. Turn off computer and unplug the power cord.

  2. Disconnect everything except the monitor, mouse and keyboard.

  3. Press power button and hold for 10 to 15 seconds.

  4. Plug power cord back into computer and press power button.

  5. Check front panel LEDs (lights) on bezel (front face) or optical drives and listen for power supply fan.

  6. If LEDs are on or power supply fan starts spinning, watch for boot screen on monitor.

  7. If computer begins to start, turn it off.

  8. Reconnect any external devices.

  9. Press the power button and make sure the computer starts.

This procedure may help the computer restart if it was shut down improperly. The process drains stored electrical energy in some critical circuits on the motherboard. These circuits start the computer properly.

Listen for beep codes

Press the power button and then listen for error beep codes. Beep patterns represent error codes indicating:

  • No computer memory found
  • A video card is missing or has failed
  • A motherboard failure
Not all desktop computers support these beep codes and the code patterns used are too varied to list. However, they can often provide a starting point for troubleshooting.

Notes:

  • Some desktop computers issue a single short beep, indicating POST has completed and the computer is attempting to boot an operating system.
  • Error beep codes are typically a pattern of beeps with an individual beep sustained for approximately a second or longer, or patterns of shorter and longer sustained beeps.
  • Typically, a beep pattern is heard followed by a pause of a few seconds and then the pattern is repeated.
  • Please use proper Electrostatic Discharge procedures when checking components such as memory or video cards.

Error Beep Code Response
Memory Three equal length beeps followed by a pause. Pattern may be repeated. Memory beeps indicate memory has either failed or needs to be reseated. Go to Check computer memory.
Thermal Four alternating beep tones (high, low) Given time to cool, the computer displays a warning message such as the following indicating that thermal or overheating event has occurred:
  • The CPU was previously shutdown due to a thermal event (overheating).
  • Contact Gateway to service computer.
Video Eight equal length beeps or a single long beep followed by two short beeps. Video beeps indicate the video card has failed or needs to be reseated. Go to Check add-in video card.
Other Other beep code patterns are heard immediately after start-up. Check both memory modules and add-in video card procedures in this checklist. If neither solves the issue, there could be a failed motherboard component requiring motherboard replacement. Follow service or replacement policies.

Beep patterns may point to memory modules or a video card that is improperly seated or faulty. Using beep patterns for proper diagnosis helps minimize No Defect Found (NDF) rates.

Check POST errors

Use Windows Vista - Desktop POST Errors or Windows XP - Desktop POST Errors checklist if computer has following symptoms:

  • Continuous operating system restart or POST looping
  • Computer locks after or during POST splash screen display
  • POST error messages
  • Hard drive and other boot device error messages
  • CMOS time/date and failed battery messages
  • Memory size decreased
  • POST warnings and other messages
  • RAID status screen is displayed for several seconds
  • Thermal or overheating messages

Remove external devices and removable storage media

  1. Start the computer.

  2. Eject/remove all media inserted into Zip drives, floppy drives, CD/DVD drives, card readers, etc.

  3. Power off the computer.

  4. Disconnect all external devices except the monitor.

    5. Note: Include keyboard, mouse, printers, anything connected to the USB ports, anything externally connected to the expansion card ports (except the monitor), speakers, microphones, etc.

  5. Plug power cord into computer and press power button.

  6. Check front panel LEDs (lights) found on bezel (front face) or on optical drives and listen for power supply fan.

  7. If LEDs are on or power supply fan starts spinning, watch for boot screen on monitor.

  8. If computer begins to boot, turn off computer.

  9. Reconnect each device one at a time, beginning with keyboard and mouse.

    Note: Make sure to power computer on and off when reconnecting each device.

  10. If computer fails to start after a device is reconnected, this device may be causing the issue. Contact the manufacturer of that device for assistance.

Ejecting Removable Media: The computer may boot or attempt to start using this media. Depending upon the state of the media and the drives in which they are inserted you may observe undesirable behavior that may seem to suggest more serious computer problems.

Disconnecting External Devices: If the computer appears to start normally, one of the devices previously plugged into the computer may have been preventing the system from starting properly.

Check monitor connections

Note: Check Product pages to see locations for all applicable connections.

  • Make sure monitor power cord properly and firmly connected to both monitor (on some models) and AC electrical outlet, bypassing any surge suppressors or UPS devices. Make sure the electrical outlet has power.

    Note: Always reconnect power cord to a known good surge suppressor when troubleshooting is complete.

  • Make sure video cable is connected to correct video port on back of computer. Make sure the video cable is correctly connected to the monitor.

  • Make sure DVI-to-VGA adapter is connected firmly between DVI port on back of computer and VGA cable connected to monitor.

  • If a different video cable is available, replace original video cable with it and retest computer. Inspect pins on original video cable to ensure none are bent, broken, or pushed inward, preventing a proper connection.

Power cord: Power cords rarely fail. If a power cord does fail, it can be easily replaced.

Correct video port: Some computers that are configured with an add-in video card have an integrated video solution. The integrated video connector is located near the rear I/O connectors such as the printer port, keyboard and mouse connectors. The add-in video card connector is located in an add-in card slot. The integrated video source located near I/O connectors is automatically disabled if an add-in video card is present.

DVI to VGA adapter: This adapter is required if monitor came with a VGA cable and video card in computer has only a DVI connector. If included with your purchase, it is located in the accessory box that came with computer.

Different video cable: By connecting a different video cable that is known to work on a different computer, you eliminate possibility of a bad connection or bad cable as the root cause of the issue. If original video cable does not appear normal upon inspection, connect it to a known good computer to check if it works.

Check monitor LEDs

Press the monitor power button and check for a video signal. Monitor has an LED on front bezel or in power button which indicates monitor has:

  • Any color - power
  • Orange, red, or blinking - No video signal from computer
  • Green or blue - Video signal from computer

If monitor LEDs are not lit after power button is pressed:

  1. Make sure power cord is firmly connected to monitor and electrical outlet.

  2. If monitor is plugged into a surge suppressor, extension cord, or UPS (uninterruptible power supply), remove it.

  3. While testing, plug monitor power cord directly into electrical outlet.

  4. Make sure the electrical outlet has power.

  5. Disconnect power cord and try a different one (if available).

  6. Press power button. If monitor starts, throw away bad power cord and get a new one.

Note: Reinstall surge suppressor once issue has been resolved and monitor is working properly.

Monitor LEDs indicate there is power to the monitor. Monitor LED color indicates whether the monitor is receiving a video signal from the computer.

Change monitor input setting

Locate input menu or press input button. Make sure correct monitor input source is selected.

Input button, typically located on side of monitor, is used to select input source.

Some monitors support both VGA and DVI input sources.

  • Blue connector - VGA
  • White connector - DVI

Note: Check the Product pages for specific location of input button and information about input menu.

Some monitors have multiple inputs such as a DVI (Digital Visual Interface) or an analog VGA input. If necessary, reference Product pages to ensure monitor has correct input setting activated. If unsure which input setting is correct, inspect the back of the monitor to see which input is being used.

Run a monitor self-test

Note: Some monitors do not support this feature.

Refer to Product pages for specific self-test procedures and follow all instructions.

Running a monitor self-test can help determine if the lack of video is because of OSD (on-screen display) settings, a faulty monitor, or the video solution.

Connect monitor to another computer

If a different computer is available, connect monitor to it to see if same symptoms occur.

If monitor is connected to a different computer with a known good video source and it still has no video, this is a strong indicator that monitor has failed. If device works normally, a secondary test can be performed by connecting monitor from known good computer to original computer to reconfirm that issue is not with monitor.

Note: If second computer is a notebook computer, be sure to observe proper procedures to enable the external video output on the notebook. On newer notebooks, this is a FN+F4 keystroke. Refer to the user guide or product documentation to confirm the proper procedures are observed to enable the external video.

Check LCD display backlight

  1. If monitor is LCD flat panel, use flashlight to diagnose failed backlight.

  2. Turn computer on.

  3. Shine a flashlight on screen from various angles and in different areas of LCD display.

  4. If you see faint images of activity, text and/or graphics on screen, replace LCD display.

  5. Follow service or replacement procedures.

LCD panels have what is referred to as a backlight, which consists of long slender lamps or bulbs on 2 or 4 edges of LCD screen. When circuitry that drives these lamps fails or lamps themselves fail, light is no longer supplied to back of screen. The information and images are still present but are no longer easily seen without an additional source of light. A flashlight can sometimes reveal faint images on screen when computer is running. If images can be seen with a flashlight, LCD backlight (tubes or the components that power them) have failed and monitor needs to be serviced or replaced.

Check add-in video card

Refer to the Product pages to identify your computer video solution.

Note: Use proper Electrostatic Discharge procedures.

  1. Turn off computer and unplug power cord.

  2. Disconnect everything except the monitor and keyboard.

  3. Place the computer on a stable work area with case cover facing up.

  4. Disconnect the video cable from the back of computer.

  5. Remove cover and locate the video card.

  6. Remove and replace video card to ensure it is properly seated.

    Important: PCI Express connectors, often used with video cards, have a retention clip. The clip is located at the end of PCI slot, not end of the add-in card, which can extend beyond slot several inches.

    For additional information, go to Product page for your computer model, select FAQs, then select How do I remove and reinstall an add-in card.

  7. Reconnect power cord and video cable, then start computer.

  8. If computer has integrated video with an add-in video card:

    1. Turn off computer and unplug power cord.

    2. Remove video card and connect the monitor to integrated video port.

    3. Reconnect power cord and video cable, then start computer.

    4. If video is working and beep codes are not heard, add-in video card is faulty. Contact Gateway for service or replacement procedures.

If the computer is new the card may have come loose during the shipping process causing the computer to not display video.

Several motherboards support a both integrated video and a slot for a higher performance add in video card. If an add-in video card is used the integrated video is automatically disabled, and a plug is inserted in the integrated video port connector. If beep codes are heard and add-in video controller failure is suspected verifying that the beeps are no longer heard, and the computer has video with integrated video connected and the add-in card removed indicates an add-in video card failure.

Check add-in cards

Note: Make sure to power computer on and off after reinstalling each add-in card and testing computer.

Make sure add-in cards are seated properly, and check for faulty cards.

  1. Turn off computer and unplug power cord.

  2. Disconnect everything except the monitor and keyboard.

  3. Place computer on a stable work area with case cover facing up.

  4. Remove cover.

  5. Find internal peripheral cards.

  6. Remove all add-in cards.

  7. Replace each add-in card, one at a time, and make sure card is firmly and evenly seated within slot.

  8. Reconnect power cord, then press power button.

  9. If all cards have been replaced, tested, and computer is working properly, removing and reinstalling cards may have resolved issue. Replace cover and reconnect all devices.

    10. -OR-

    If computer fails to start after a particular card is installed, that card may be causing computer to fail. Refer to service or replacement procedures.

It is possible for peripheral cards to become unseated while moving the computer or during the shipping process. If computer has been recently opened and cards had been removed and replaced, a card might not be fully or properly seated in its slot. If computer begins to function normally after a new or existing peripheral card has been removed, it is possible that the peripheral card has recently suffered electrical damage of some kind and is preventing the computer from starting properly. Even new peripheral cards can be faulty or damaged.

If a card identified as the cause of the problem is not a Gateway product, instruct the customer to contact the manufacturer of the card for support.

Check all internal drives

  1. Turn off computer and unplug power cord.

  2. Disconnect everything except the monitor and keyboard.

  3. Place computer on a stable work area with case cover facing up.

  4. Remove cover.

  5. Find internal drives.

  6. Unplug power cables and data cables from all drives.

  7. Connect power cord and keyboard, then press power button.

  8. If computer starts correctly, turn off computer.

  9. Reconnect each drive one at a time.

    Note: Make sure to power computer on and off when reconnecting each drive.

  10. If computer fails to start after connecting a specific drive, the drive may be damaged and should be replaced. Contact Gateway for service or replacement procedures.

If computer begins to start successfully when drives are unplugged, one drive may have a short circuit or internal electrical problem preventing computer from starting properly. If a second desktop computer is available, install bad drive in second computer. When bad drive is installed, second computer should have similar or exact symptoms.

Check memory modules

  1. Turn off computer and unplug power cord.

  2. Disconnect everything except the monitor and keyboard.

  3. Place computer on a stable work area with case cover facing up.

  4. Remove cover.

  5. Find memory module(s).

  6. To reseat memory in each slot, place thumbs on either side of module, and press module down until retaining clips fully lock into place.

  7. Reconnect power cord, then press power button.

  8. If computer begins to start, turn it off. Replace cover and reconnect any external devices.

    -OR-

    If computer does not start, turn the computer off.

  9. Replace memory modules one at a time.

    1. Pull retaining clips outward from memory module to release it and lift straight up.

    2. Make sure retaining clips are pushed down to side.

    3. Insert memory module into socket, make sure notches on module and socket clips align.

    4. Place thumbs on either side of module and press module down until retaining clips fully lock into place.

    Note: Make sure to power computer on and off when installing each memory module. If computer fails to start after a peripheral card is reconnected, this module may be causing issue.

  10. If all memory modules have been replaced and computer is working properly, removing and reinstalling memory may have resolved issue. Replace cover and reconnect all devices.

  11. Check for bad memory modules or bad memory sockets.

    1. Install memory module in either (but not both) end slot (slot selected is only a starting point).

    2. Power up computer. If beep codes are no longer heard, memory module is good.

    3. Remove installed module, repeat with each memory module.

    4. If all modules failed (beep codes were heard), repeat using each memory slot.

  12. If any of the memory modules work in one slot but not the previously tested slots, the motherboard is probably bad. Contact Gateway for service or replacement procedures.

    -OR-

    If any of the memory modules work in one slot but not all the modules work in that slot the failing modules may be bad or incompatible with the computer. Contact Gateway for service or replacement procedures.

    -OR-

    If memory modules do not work in any slot, it is possible that all memory modules are bad, any replaced or added memory modules were incompatible with the computer (check product for memory module requirements), or that the motherboard is bad. If possible, try a new or known good memory module to determine whether it's a motherboard problem.Contact Gateway for service or replacement procedures.

The internal components of the computer are sensitive to ESD (electro static discharge). Damage to the motherboard, memory modules, and peripheral cards can occur if these parts are exposed to ESD. Memory does not often go bad if left alone. When it does fail, error beep codes can usually be heard coming from the motherboard. If the memory had been handled recently without proper ESD grounding it could have been damaged by ESD and will need to be replaced.

If new memory has recently been added, remove the new memory and see if the computer starts and runs normally without the new memory installed. The added memory modules may be incompatible with the computer, or may have been damaged by being handled, etc.

If following the above procedures did not resolve your problem, please contact Gateway through one of the following methods: