Troubleshooting Common Hardware Problems – CompTIA A+ 220-901 – 4.1

Troubleshooting hardware can be a challenge, especially considering all of the things that could possibly go wrong. In this video, you’ll learn about some of the most common hardware problems and how to quickly solve them.

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When you’re using your computer, there’s really nothing more unexpected than having your entire computer turn off suddenly. It suddenly is a black screen. You don’t have any error messages. There was no warning. You were working fine, and then suddenly your computer turns itself off.

Unfortunately, there are not many things you can do at that point other than to turn the computer back on, and hopefully there might be something written in the Event Viewer in Windows. You might also want to see if your system is getting so hot that it’s automatically turning itself off to help protect the components.

This is especially true if you’re using applications that use a lot of CPU or graphics capability. And they’re going to heat up your system that much faster. Make sure to check all of your fans to be sure that they’re spinning. Make sure there’s nothing preventing the air flow from going through your computer.

You might also want to check the heat sinks. Make sure none have fallen off and that they’re all connected securely to the components.

If your BIOS is able to provide you with temperature information, you might want to boot up to the BIOS before restarting your operating system to see what the internal temperatures are inside of your computer.

Unexpected shutdowns might be caused by failing hardware. If you’ve added new hardware to your system, it might be worthwhile to remove it and see if the problem still exists. You could also check Device Manager in Windows or run the hardware diagnostics that comes with your computer to see if everything is working exactly the way it should be.

Because there is so little warning and usually no error message that you can reference with these unexpected shutdowns, it becomes a lot more difficult to troubleshoot. So what you may want to do is find out what’s working and start eliminating one thing after another until you find the single component that’s causing these unexpected shutdowns.

A lockup is similar to an unexpected shutdown because your computer suddenly becomes unavailable. It suddenly stops working. But the screen doesn’t go black. Instead, everything just freezes. You’re not able to move your mouse. You’re not able to type anything on the keyboard. You simply have a machine that’s no longer operating the way it should be.

It might be useful to look for any type of activity. You want to check the hard drive access lights. Maybe there’s some status lights. Try Control Alt Delete and see if you can prompt your operating system to get through whatever’s hanging up the OS and see if you can at least get to a point where you can use some part of the computer.

If you’ve updated drivers recently, you might want to roll back to a previous version. Or if you haven’t updated recently, it may be time to make sure you have the latest drivers installed. Check for any software patches or anything else that might update your system to get around some of these lockups.

You might also want to monitor the resources you’re using on your computer. Make sure you always have enough hard drive space and that you always have enough memory available. If you begin to run low on these resources, your system may become unstable.

And again, we’re not completely certain the problem is related to software. It could certainly be hardware as well. So it’s useful to run a hardware diagnostics to make sure that all of the hardware is operating as expected.

When you first turn on your computer, it runs through a POST. This is a Power On Self Test. It’s a very basic test of the hardware in your system to make sure everything is available and working properly. It’ll check and make sure CPU is installed and working. It’ll check for video access, and it’ll make sure that memory’s installed on the motherboard.

If there any problems during the Power On Self Test, it’s very common for your BIOS to put a message on the screen and to send out a series of beep codes. These are long and short beeps that it might use to designate what a particular error is referring to.

It’s not necessary to memorize every manufacturer’s set of beep codes because every manufacturer has a different set, depending on what the error might be. Instead, you should recognize what a beep code is and what it’s referring to and then reference the manufacturer’s documentation to get more detail on that specific code.

If you’re booting up your computer, and you get no video at all, your Power On Self Test is probably going to recognize that there’s a problem with the video subsystem. In those cases, it obviously can’t display a message on the screen, so it’s going to use these beep codes to be able to designate that there’s some type of video problem. This might also indicate that there are problems with the BIOS configuration, so you may want to reference what your settings are for video in the BIOS and see if that might fix the problem.

Once the Power On Self Test is complete, your system then begins to boot the operating system based on what’s listed in the BIOS. The BIOS will have a list of all of the different storage devices in your computer, and they’ll be listed in order of what is booted from first, what is booted from second, and what would be booted from in third.

If your BIOS is not configured with the storage devices in the correct order, you may not be booting from the device you think you’re booting from. In fact, you might get an error message that says there’s no operating system on the storage device, when in reality, it’s trying to boot from your DVD-ROM instead of booting from your hard drive or your SSD. You’ll want to enter the BIOS configuration, look at what devices are configured in the boot order, and modify those as required.

Another frustrating problem is when your computer boots up, and it gets to a certain point, and then it restarts itself and goes through the boot process again, only to repeat the process over and over again. When this occurs, it’s useful to know how far the boot process is getting. Do you only see the BIOS setup screen? Do you get the operating system splash screen? Are you getting any other type of diagnostic messages? And once you have this information, you’ll have an idea of just where the problem might be occurring during the rebooting process.

If this is something that is related to a bad driver configuration, you may be able to press F8 as Windows is loading and choose to use the last working configuration. By booting with the last working config, you can bypass any of those previous changes you made to the drivers.

You might also want to try Safe Mode. Again, press F8 as Windows is starting and choose to start in Safe Mode. If this works properly, you may be able to disable things like automatic restarts within the Windows operating system so that it will stop and at least give you an idea of where the problem might be occurring before everything restarts, and the screen goes black again.

If this is related to new hardware that you’ve added to your system, it may be time to remove that to see if the problem is still there. Or if you have hardware that’s going bad, you might want to remove or replace one device at a time. This might be a good time to reseat all of the hardware components or to run a hardware diagnostics to see where the problem might be occurring.

If you plug in your computer, you hit the power button, and nothing happens, then you’re getting no power and no lights and no messages to your computer. You might want to then check how the power is getting to your computer. You obviously want to check power at the source. Maybe you have an outlet tester like this that you can plug in. Or grab your multimeter and connect it to the power source to see exactly what the voltages are coming from the wall.

You might also want to check the power supply that’s inside of your computer. It may be receiving the correct voltages from the wall, but it’s not sending any of the power to the motherboard. Or maybe it’s not sending enough power to get things started. You want to grab your multimeter again and check those connections as the power supply is plugging into the motherboard with a 24-pin power connector.

Another odd problem with power might be that you start your computer, and you can hear the fan spinning up, but there’s no other sign of power. There’s no status lights, and you see no messages on the screen. You might have a bad motherboard. If you’re not getting a POST screen, then there’s definitely a problem with that motherboard getting started.

If the fans are spinning up, it may be that the fans are directly connected to the power supply instead of being connected to the motherboard. In that case, it’s obvious why the fans are working, because they’re bypassing any problems that might be on that motherboard.

The case fans also have a lower voltage requirement, so they might be able to run, but your motherboard may not have enough voltage to get going. It’s a good idea then to check the power supply that’s inside of your computer and make sure that it’s providing all of the different voltages across all of the rails of your computer.

One constant challenge we have with our computers is the heat that builds up inside of our computer cases. This heat is created by our CPUs, our video adapters, our memory, and all of the other components that are inside of our computer.

We rely on the cooling systems inside of our computer to make sure that everything is going to remain at the proper temperatures. We have fans that are pulling air through our computer. There are heat sinks connected to the different components inside of our computer. We want to be sure that all of these components are free of dust buildup, like you would see in this picture, so that you’re able to get all of the air flow moving properly through your computer.

You could even use some different software to be able to monitor this. One good example might be built into the BIOS itself, so you can see the temperature inside of your case. Or try some software like HWMonitor from This could be one of the easiest troubleshooting sessions, although it does get a bit dirty when you start cleaning off some of this dust. But if you can remove all of this and get the airflow moving again, you’ll find that your computer is able to keep everything nice and cool on the inside of the case.

What you don’t want to hear inside of your computer is any type of loud noise. There should simply be the hum of the fans as they’re pulling air through your system. You don’t want to hear any type of grinding or loud noises. If there are loose components, you might hear rattling when you’re moving your laptop or your desktop computer around. So make sure that everything is exactly where it is on the inside of the computer case.

If you do hear any type of scraping or grinding, it might be indicative of a hard drive problem. Make sure you have all of your data backed up, and this may be a good time to take the case off and really listen to where this grinding noise is coming from.

If you’re hearing a clicking noise, it might be a fan that’s hitting a cable or a wire that’s inside of your computer case. You might want to check and make sure that everything is able to flow properly and that your fans are able to spin inside of the computer case.

And one of the sounds you really don’t want to hear is a popping noise followed by smoke and perhaps the smell of smoke. In those cases, you may have blown a capacitor. Here’s an example of some capacitors that have blown. You can see that some of these are a little bit bulged on the top. Some of them may be deformed, or they might have blown completely off, whereas other capacitors are completely flat and have no deformation of the shapes. So it should be easy to visually see where a bad capacitor might be in your computer without having to do any additional tests.

One challenging hardware troubleshooting task is when you have a device that’s working fine, and then it stops working, and then it starts working again, and then it stops working. It is intermittently working properly, and then intermittently not working the way you would expect.

This could be caused by a bad installation. You might want to remove the component and insert it back into the computer. Maybe check it, and make sure that it’s seated properly. And make sure that you use all of the screws that come with the device to make sure that it’s going to be properly seated to the motherboard.

You might also have some bad hardware. This can happen if there is a bad connection or maybe there’s a lot of heat and vibration, and you have a device that simply isn’t working the way you would expect. You’ll need to replace that piece of hardware, then, to be able to avoid these intermittent device failures.

Many high-end motherboards will have some indicator lights or even codes that are shown on the motherboard as the system is booting. That way, if you have any problem with the boot process, you’ll know exactly where the problem’s occurring because an error message is displayed on the motherboard.

But there are other indicator lights that you can reference. You can see if the power light is turning on. That way, you know if there’s power coming from the power supply to the motherboard itself. You might want to look at a network interface and see if there is a link light. See if you’re actually connecting to the switch that’s on the other side of that cable. There might also be a second light on the network connection showing you what speed or activity there might be as information is going out of the network and back in again.

It’s said that our computers are run with smoke, and when the smoke gets out, the computer stops working. If you’re having some type of electrical problem inside of your computer case, and you do see or smell smoke, then there’s probably an issue you need to resolve. You should always disconnect the power from your computer when these situations occur because there should never be a smell or a burned odor coming from your computer.

You might want to open up your case and look for the components that may have caused this problem. There might have been a bad capacitor or a component that’s simply burned out. It should be relatively obvious that there is a discoloration with that particular component. That way, you’ll know exactly which one to remove and replace before you power back on.

One of the worst things that you’re going to see in a Windows environment are these Windows crash screens. These are going to occur when some type of problem has happened that will not allow the operating system to continue. This is also called a Windows stop error, and it’s going to give you more details about where this particular problem is occurring.

Some people call this the blue screen of death, although newer Windows versions don’t use exactly this same type of screen to show information. And there are a lot of interesting and important details inside of this stop error.

All of this information is also written to the event log, so if you don’t catch exactly what was on the screen before you restarted, you can always refer back to the logs to see what happened. You might want to always make a reference of what is being shown on this screen so that you could do more research about what might have caused this particular problem.

Here is an example of some of the details you can get from a Windows stop error. At the top, it tells me exactly the file that’s causing this problem, SPCMDCON.SYS. And it tells me that it had a page fault in nonpaged area.

You might also want to make a reference of the stop error itself and some of the memory addresses, and of the driver down here and those memory addresses as well.

If you’re working with an Apple computer running Mac OS, then you’re probably familiar with the spinning ball of death. Your day’s going normally. You’re using your applications. And then the ball of death begins. And while this ball is spinning around, you’re not able to perform any type of functions on your computer. And you have to wait now to see is this going to continue indefinitely, or is your system going to suddenly allow you back access to the operating system.

The proper term for this spinning ball of death is the Mac OS 10 spinning wait cursor. The operating system is giving you feedback that something else is happening in the operating system right now, and it needs to perform that function before you can continue.

The problems you have with this is when it starts to spin, but it never stops. And in those cases, you’re going to have to restart your computer to regain control of the operating system.

There could be many reasons for this spinning wait cursor. One might be related to a bug in the application. You might have bad hardware in the computer that you’re using. Or there might be some slow paging to the disk, and you’re having to wait for the system to finish the paging before you’re then able to continue operations.

If your system never recovers from the spinning wait cursor, then your only option is to restart the system. There will probably be information in the console logs that can tell you why this particular system locked up, and you might be able to troubleshoot and resolve the issue from there.