Which of these would not cause any issues with the power on self-test (post)?

Summary: This article is a guide to identifying and resolving start-up / power issues with your Dell personal computer. (These include No Power - No signs of life, No POST - Diagnostic LEDs or Beeps, No Boot - Cannot load Operating System and No Video - personal computer starts but nothing that is seen on the display.)See less This article is a guide to identifying and resolving start-up / power issues with your Dell personal computer. (These include No Power - No signs of life, No POST - Diagnostic LEDs orSee more

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Summary: This article is a guide to identifying and resolving start-up / power issues with your Dell personal computer. (These include No Power - No signs of life, No POST - Diagnostic LEDs or Beeps, No Boot - Cannot load Operating System and No Video - personal computer starts but nothing that is seen on the display.)See less This article is a guide to identifying and resolving start-up / power issues with your Dell personal computer. (These include No Power - No signs of life, No POST - Diagnostic LEDs orSee more
Article Content
No Power For Desktops or All-in-One PCs:
No Power For Laptops:
No POST For Desktops or All-in-One PCs:
No POST For Laptops:
Further Information
Article Properties
What are the main causes of a failed power on self
What controls the Power On Self
What does the POST Power On Self
What is the POST Power On Self

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Article Content

Symptoms

This video is a great starting point to help identify which of the following sections you should use to troubleshoot further:

My Computer Does not Start

Duration: 01:21
Closed captions: English only

Cause

NOTE: Click the title of the section that you want to open below, to see the contents.

No Power For Desktops or All-in-One PCs:

Computers have a power light LED that glows when it is receiving power.

On Desktops, the front panel of the computer case has LED near the power button.

Try these quick steps to recover your Dell computer from a power issue.

Try the following steps to resolve a desktop not-powering situation (There are more detailed instructions in the troubleshooting link below.):

Problem DescriptionSuggested ResolutionThe computer is either turned off or not receiving power.

Reseat the power cable in the power connector on the back of the computer and the electrical outlet.
Bypass power strips, power extension cables, and other power protection devices to verify that the computer turns on properly.
Ensure that any power strips being used are plugged into an electrical outlet and are turned on.
Ensure that the electrical outlet is working by testing it with another device.
Use a verified working Power cable.
Ensure that the main power cable and front panel cable are securely connected to the system board.
All power supply units include a self-test ability in an isolation mode. A test button and LED are on the side of the unit where the AC plug is located. Ensure that the power cable is connected to the supply and press the test button to test the PSU.
If the PSU LED does not illuminate, remove the PSU cables from the system board and test again. If the LED still does not illuminate when the test button is pressed, the PSU is possibly faulty.
If after removing the cables from the system board and the PSU LED illuminates, one of the attached devices or components could be faulty. Remove all attached components, reattach the PSU cables and using the PSU test button, install each component individually to test.
Install a verified working PSU.

NOTE: Certain Dell All-in-One PCs may have a separate power adapter.

If you have identified a No Power issue? You can find out more information and troubleshooting help on this issue by using the article that is linked below:

Here is a quick video that covers all the reasons why your desktop is not starting up.

Power issues on Desktop computers

Duration: 01:15
Closed captions: English only

NOTE: Power cords that are supplied for a monitor may be different based on the Vendor, Dell Monitor power cables are interchangeable with the Dell Desktops.

No Power For Laptops:

On laptops, the indicator that power is reaching the computer can be a lit LED power button. Alternatively, it may be an LED located in the upper part of the keyboard or along the front edge of the computer itself.

Try these quick steps to recover your Dell computer from a power issue.

Try the following steps to resolve a laptop no power situation:

NOTE: Some models of Notebook such as the Ultrabook models may not have a removable battery. If you check your manual and it does not have your battery as a removable part, then move straight to step 5.

Here is a quick video that covers the reasons why your laptop is not starting up.

My Dell in 99 seconds: Cannot turn on your laptop

Duration: 01:46
Closed captions: English only

Once you have identified a No Power issue, you can find out more information and troubleshooting help by checking out the articles that are linked below:

NOTE: The M-BIST test has been built into the Dell family of laptops starting with the Latitude XX90 series of computers.

M-BIST - Built-in Motherboard Self-Test toolEvaluates the health of the motherboardM-BIST is designed to operate even if there is no video, no fan, or no hard drive spin-up (new mainboard diagnostic). These symptoms are typically described as No Power, No Video, or Dead System.Press and hold the M key and the Power button down simultaneously:

If an error is detected the Battery status LED lights up Amber and you need to contact us.
If the Battery status LED does not light up, then no fault is detected with the motherboard.

The term POST refers to Power-On Self-Test, which is a series of checks the computer goes through whenever it starts. If the computer fails any of these tests, it stops the start-up process and report a fault. Troubleshooting across Desktops, All-in-One PCs and Notebooks use the same procedures, but different reference material.

Try these quick steps to recover your computer from a POST or startup issue.

No POST For Desktops or All-in-One PCs:

Indications of a failed POST include:

If the computer is displaying the Dell logo and does not move past that point, it has probably failed POST.
If the power light lights up and it is amber or orange, this is usually an indicator that it has failed POST. Note down if there is a particular pattern in which it beeps or flashes.
If you see the text on a black screen, the computer is performing the POST. If the computer stays in that condition and does not move past it, it has probably failed POST.
If the video screen displayed anything at all during the startup process but is now black, this probably indicates that the computer failed POST.

If the computer is not beeping and the Diagnostic LEDs are not flashing or lit? Unplug all connections and remove all media communication devices (for example external monitors). Reconnect one at a time and check if the computer functions.
For a Desktop at the Dell logo screen, tap the F12 key. Enter the One Time Boot Menu and use the arrow keys to highlight Diagnostics and press enter. Some Desktops do not have an F12 key, to access the boot options you have to press the <0> (zero) key at the Dell logo screen.

For information about running and using the ePSA Diagnostics, please check out our:

No POST For Laptops:

Indications of a failed POST include:

If the computer is displaying the Dell logo and does not move past that point, it has probably failed POST.
If the computer is beeping or if Diagnostic LEDs, Caps/Num/Scroll Lock LEDs are flashing? Note down if there is a particular pattern in which it beeps or flashes. This is usually an indicator that it has failed POST.
If you see the text on a black screen, the computer is performing the POST. If the computer stays in that condition and does not move past it, it has probably failed POST.
If the video screen displayed anything at all during the startup process but is now black, this probably indicates that the computer failed POST.

If the computer is not beeping and the Diagnostic LEDs and caps/num/scroll lock LEDs are not flashing or lit? Unplug all connections and remove all media communication devices (for example external monitors). Reconnect one at a time and check if the computer functions.
For a laptop, press and hold the key and then press the power button. This starts the preboot testing and will launch ePSA.

For information about running and using the ePSA Diagnostics, please check out our:

If you are looking for more information and troubleshooting help to continue resolving this issue, you can use the article that is linked below:

After the computer completes the Power-On Self-Test, it will attempt to boot the operating system.

If the computer advances past the Dell logo screen and then hangs attempting to load the operating system? It is most likely a No Boot issue. Troubleshooting this issue uses the same procedures across Desktops, All-in-One PCs, and Notebooks.

Try these quick steps to recover your computer from a boot problem.

Follow the Video Guide Below.

My Dell in 99 Seconds: System Frozen at the Dell Logo

Duration: 01:46
Closed captions: English only

To rule out any hardware problems, you should run the integrated ePSA diagnostics.

Most No Boot issues come down to operating system issues. Choose the article appropriate to your Operating System and troubleshoot this further:

If the computer is reporting a specific fault on-screen about the Hard Disk Drive, then you can Troubleshoot further on one of the links below:

If the power indications are normal, but there is never any video that is seen on the computer's display during the startup process? This probably indicates a No Video issue.

NOTE: For Desktop computers - Remember that the monitor has a separate power supply. Ensure the monitor has a power LED indicator showing that it is turned on.

NOTE: Certain Dell All-in-One PCs can be connected to an external monitor using VGA, HDMI, or DisplayPort connectors. This feature may vary across different models. See the User Manual of your Dell personal computer.

Try these quick steps to resolve video issues on a Dell computer.

Troubleshooting a No Video issue:

Problem DescriptionSuggested ResolutionThe desktop computer is in a normal on condition.
The diagnostic lights are not lit after the computer successfully boots to the operating system but there is no display showing.

Ensure that the display is connected to the correct port and turned on.
Ensure that the display data cable is not damaged and replace if necessary.
Ensure that the correct Input Source on the display is correctly selected.
Remove the data cable from the computer. A Self-Test box should appear on the display.
If the Self-Test box does not appear on the display, replace the display with a verified working unit.
If there is still no display showing, check if video was shown during the POST routine.
If video was shown during POST, the display or graphics driver could be the cause.
Restart the computer into Safe Mode. To load Safe Mode, press and hold the F8 key as your computer restarts.
This loads the Advanced Boot Menu. Select Safe Mode. Install the current versions of the display and graphics card drivers. Restart the computer, and check for video.
If available, replace the graphics card with a verified working card.
If both graphics card and monitor work ok on another personal computer, then contact technical support to resolve the problem.

NOTE: For Notebooks, press and hold the key and then press the power button. This starts the preboot testing and will launch the ePSA diagnostics. The ePSA's will test your video with a series of patterns.

My Laptop Display Will not Turn on

Duration: 01:46
Closed captions: English only

If they look fine, but you want to test more? You can respond to the video test by pressing the letter and ePSA will then launch the LCD BIST test. If you have a no video issue? You can either run the keyboard shortcut to enter the ePSAs or keyboard shortcut to run the LCD BIST from POST.

How to Test Your Dell Laptop Screen

Duration: 00:24
Closed captions: English only

NOTE: Two new diagnostic BIST tests have been built into the Dell family of laptops, starting with the Latitude XX90 generation of computers.

M-BIST - Built-in Motherboard Self-Test toolL-BIST - Built-in LCD Power Rail Self-Test tool.Evaluates the health of the motherboardChecks if the motherboard supplies power to the LCD.M-BIST is designed to operate even if there is no video, no fan, or no hard drive spin-up (new mainboard diagnostic). These symptoms are typically described as No Power, No Video, or Dead System.L-BIST is designed to test when seeing the symptom of No Video.Press and hold the M key and the Power button down simultaneously:

If an error is detected the Battery status LED lights up Amber and you need to contact us.
If the Battery status LED does not light up, then no fault is detected with the motherboard.

Press and hold the Power button down:

If there is no display and an error is detected. The Battery status LED flashes 2 x Amber and 8 x White, and you need to contact us.
If there is no display and the Battery status LED does not light up, then no fault is detected with the motherboard.

Resolution

Further Information

Clearing CMOS/NVRAM on your personal computer:

The RTCRST jumper allows you to clear NVRAM. The NVRAM is cleared when the jumper is closed. (You can use the jumper from the password bridge.) Remember that it is always best practice to remove the power cable from the personal computer before opening the lid or access panel and going inside. To clear the CMOS, AC power must be applied to the computer for about 10 seconds while the jumper is closed. (This does not necessarily mean turning the computer on, putting power across the motherboard is enough.) Browse to Clearing CMOS via removing and reseating the CMOS battery for visual guides to this process.

Pins 1-2 shorted clears NVRAM

Warning: Resetting CMOS on most platforms clears the Management Engine BIOS Extension (MEBx) settings including the MEBx password and all configured settings.

Disconnect the external power from the personal computer.
Remove the computer cover.
Locate the 2-pin password connector (PSWD) on the system board.
Remove the 2-pin jumper plug.
Locate the 2-pin CMOS jumper (RTCRST) on the system board.
Move the 2-pin jumper plug from the PSWD pins onto the RTCRST pins for approximately 5 secs.
Return the 2-pin jumper plug to the PSWD pins.
Replace the computer cover.
Connect your computer to main power again, and turn it on.

Common issues:

These 4 (four) issues are the most common reasons why you would be troubleshooting a problem outside of your Operating System.

They break down into 3 (three) outcomes:

You identify a hardware issue that reseating does not resolve and contact us to arrange a repair.
You identify a software issue and either resolve the issue or contact us for a resolution.

Going through the troubleshooting results in fixing the fault, without a clear reason why.

Additional Information

Visit our Battery and Power site for additional resources and information.

More information and support for your Dell monitor, laptop or tablet screen can be found on our Monitor Support site.

Out of warranty? No problem. Browse to the Dell.com/support website and enter your Dell Service Tag and view our offers.

NOTE: Offers are only available for US, Canada, UK, France, Germany, and China personal computer customers. Server and Storage are not applicable.

Article Properties

Affected Product

Chromebox, Alienware, Inspiron, Retired Models, OptiPlex, Vostro, XPS, G Series, Chromebook, G Series, Alienware, Inspiron, Latitude, Vostro, XPS, Retired Models, Fixed Workstations

What are the main causes of a failed power on self

If the power-on self-test is unsuccessful, it generates a beep code to indicate the error encountered and the computer will not boot up. All computer POST errors are related to hardware issues with one of the components in the computer.

What controls the Power On Self

POST doesn't rely on any specific operating system. In fact, there doesn't even need to be an OS installed on a hard drive for it to run. This is because the test is handled by the system's BIOS, not any installed software.

What does the POST Power On Self

Power-on self-test (POST) performs tests on workstation core components such as CPU and memory. POST checks low-level interaction between the CPU, caches, memory, JBus, and the I/O bridge chip. Typing the post command from the ok prompt initiates tests that check the CPU, I/O bridge chip, and memory modules.

What is the POST Power On Self

The POST (power on self-test) is a set of procedures that a computer runs through each time it is turned on. It ensures that all of the system's hardware is working properly before trying to load the operating system. If the computer does not pass POST, it will not boot.