3.4.1-3.4.2.txt

In this lesson, we’re going to discuss several common issues with motherboards, CPUs, and system memory. We can’t possibly cover every possible issue in this lesson. Instead, we’re going to focus on several of the more common issues and their causes. Power Issues 0:17-1:06 Let’s begin by reviewing c...

In this lesson, we’re going to discuss several common issues with motherboards, CPUs, and system memory. We can’t possibly cover every possible issue in this lesson. Instead, we’re going to focus on several of the more common issues and their causes. Power Issues 0:17-1:06 Let’s begin by reviewing common power issues that can affect system motherboards. Power supplies wear out over time, especially if they’re overheated or overstressed. If the power supply can’t deliver the DC electricity that the system needs, the system may exhibit one of several behaviors. It may unexpectedly shut down, it may continuously reboot, or it may not power on at all. Remember, pin 8 on the power supply connector connects to the power good wire on the motherboard. If power disappears off that wire, the motherboard shuts down. If power quickly reappears on that wire, the system may attempt to come back on by itself, which causes the symptom of continual reboots. If it doesn’t, then the system will just shut off. It’s also possible that a bad power supply cannot provide enough voltage on this wire for the system to even boot at all. This results in the failure to power on symptom. Power Supply Test 1:07-1:38 You need to verify that it is truly the power supply that is causing the problem. Test the power supply and determine whether or not the power supply is providing enough voltage for the system to power on. Turn the power supply on and then test the voltage being supplied on either a motherboard connector or on a hard disk connector. For example, anything less than about 11 volts on a 12-volt wire indicates the power supply is failing. If this is the case, purchase a new power supply, remove the old power supply from the system, mount the new one, and plug it in. That should fix the power issues that you’re having. Boot Errors 1:39-2:13 When troubleshooting the motherboard, CPU, and memory issues, there may be times when you have to deal with boot error codes. Every time the PC boots, it runs a power-on self-test, or a POST. POST checks to make sure that all of the basic hardware in your system, such as the system memory, keyboard, CPU, chipset, and so on, is present and functioning at boot time. If it finds a problem during POST, an error is registered. How this error is reported depends on the motherboard manufacturer. Several different methods have been used over the years: audible beeps, numeric codes, and error messages. Boot Beep Codes 2:14-2:36 Error messages displayed on the screen are much easier to diagnose than more cryptic error code numbers or beep codes. If you have a system that’s using beep codes, you’re going to have to research to determine what they mean. For example, you find that three beeps, two beeps, and then four beeps indicates a keyboard failure. The actual codes used will vary, so check the motherboard documentation on the manufacturer’s website. Boot Error Codes 2:37-3:00 Instead of beep codes, some manufacturers may display an error code on the screen. These codes vary by manufacturer, just like beep codes. If you see an error code displayed on the screen after POST, you need to go to the motherboard manufacturer’s website to find out what that particular code means. For example, a 201 error may indicate a memory problem, while a 301 error indicates that the keyboard did not respond correctly. POST Card 3:01-3:32 Sometimes, a computer system may experience problems, such as a malfunctioning video adapter, that can prevent you from seeing error codes displayed during POST. If this is the case, you can use a POST card to access the POST error codes. A POST card is an expansion board that you insert into an expansion slot. Some POST cards also include a USB interface that allows you to connect them to computers that don’t have expansion slots, like a notebook system. Most models provide an LED display to report any error codes generated during POST. Distended Capacitors 3:33-3:53 If the fans in the power supply start, but no power reaches the other devices and the system doesn’t enter POST, it’s possible that you have a problem with distended capacitors. Inspect the various capacitors on the motherboard. If you see that any are swollen on top or are leaking brown liquid, that means you’ve got blown capacitors and you’re going to have to replace the motherboard. Interruption of CMOS Power 3:54-4:38 Another common problem is one where the system loses time or you lose your settings out of the BIOS or UEFI. For example, you may power on the system and see that the date and time are wrong and that the system has defaulted to the factory default settings. To troubleshoot this problem, you need to remember that constant power is required to store the settings that you configure in your BIOS or UEFI. The motherboard also needs constant power to keep the system clock running. If the power to the BIOS or UEFI is interrupted, then all settings are lost and the system resorts to the default factory settings. It may also cause the real-time clock to reset to a date and time many years in the past. If this happens, then it’s likely that your motherboard battery has gone bad and it needs to be replaced. Overheating 4:39-5:48 Now, let’s talk about system overheating. In a modern system, the system components generate a lot of heat that needs to be dissipated. Overheating causes premature component failure. Overheating could be caused by a variety of different factors. Inadequate airflow may be the result of having an inadequate number or size of fans in the system. You can add extra fans to the system to increase airflow. Improperly installed fans can affect the airflow. All fans must be oriented to force air through the system in the same direction. You can change the direction of the airflow by flipping a fan 180 degrees. Failing fans push less air than a properly-functioning fan. You can easily identify a failing fan by the screeching noise they commonly make. This can be fixed by simply replacing the failing fan. Excessive dust within the system can block airflow and cause overheating. You can use compressed air or an anti-static vacuum to remove dust buildup. Environmental issues can also cause problems. If the air temperature outside the computer is already overly warm, then the temperature inside will be overly warm too. You should implement a proper HVAC system in your work area to remove excess heat from the environment. Temperature Monitoring 5:49-6:34 As a PC technician, you need to monitor the internal temperatures of your systems. Most motherboards include one or more sensors that you can use to monitor the temperature. Usually, you can view the current temperature within the BIOS or UEFI setup. There are also several software applications available that can monitor temperature as well. These tools can pull the current temperature value from the sensors and display it on the screen. Unlike using the BIOS or UEFI utility, these tools allow you to dynamically monitor the temperature as the system is being used. Most motherboards include a thermal shutdown feature. If the system gets too hot, the thermal shutdown feature immediately shuts the system down to prevent permanent damage. However, it usually doesn’t do so cleanly, and there is a risk of data corruption as a result. Intermittent Device Failure 6:35-7:24 Another common problem that can happen is intermittent device failure. This happens when a device in the system just stops working from time to time. This usually indicates that the device itself is failing. The best remedy is just to replace the failing device. At some point in the future, the flaky component will fail completely. Therefore, it’s better to just replace it immediately. However, it is possible that an intermittent failure is being caused not by a failure in the device itself but by the device driver that’s used by the CPU to communicate with that device. Device drivers are just software and occasionally they have bugs. Before you replace a device experiencing intermittent failures, you should first verify that the latest drivers have been loaded for that device. Sometimes downloading the latest driver and installing it will solve the problem. If it doesn’t, then go ahead and replace the device itself. Smoke or Burning Smell 7:25-8:03 Let’s end this lesson by discussing what to do in the event of smoke or a burning smell. Both of these symptoms indicate that electricity in the system isn’t flowing in the correct paths and it’s going somewhere it’s not supposed to go. If you see or smell smoke, shut the system off immediately. There’s a variety of issues that could cause this issue. It could be caused by a connector that isn’t seated all the way and the electricity is arcing between the two ends. It could be caused by a short-circuit in the printed circuit board of the motherboard itself or on an expansion board. Unfortunately, if you see or smell smoke, it’s usually too late. It’s unlikely that the components that were affected will ever work properly again and they will need to be replaced. Summary 8:04-8:11 In this lesson, we talked about common issues with motherboards, CPUs, and RAM. We talked about power issues, BIOS or UEFI issues, cooling issues, and intermittent device failures. Previous Resource 3.4.2 Motherboard Troubleshooting Facts Next Resource This lesson covers the following topics: Hardware symptoms Software symptoms Sensory symptoms Whenever you have a problem with a computer, don’t panic! There is a saying that every troubleshooting challenge begins with a Windows reboot: Ctrl + Alt + Del. After that, be sure to use a systematic approach and write down the steps you take. Hardware Symptoms The following table discusses common hardware symptoms and possible solutions. Symptom Description Black screen A black screen with only a white cursor or continuous reboots before login indicates a fatal system error has occurred. The system had a major problem and forced the operating system to shut down. This can happen because of a corrupted device driver, faulty hardware, or Window’s software glitch. Take these steps: Disconnect non-essential peripherals to the PC and try rebooting. If you get a black screen with spinning dots during startup it means an update is installing. If it never completes, there could be a compatibility problem. You can try updating the drivers to resolve the problem. Disable all non-essential applications and put them to sleep automatically. This allows you to get the most out of resources, such as RAM and CPU. Then, try rebooting. Reset to default settings using core BIOS/UEFI configurations by interrupting startup. Ensure the Boot Priority is the hard disk. Try rebooting. Launch a Windows repair and perform a system restore. Try booting into Safe Mode. If the screen goes black after the operating systems loads and seems to be working properly: Double-check all physical and configured connections on the device and display including power, video port, video card, etc. Also try using a different display monitor and cable. Detect the display and check the brightness setting. On Windows 11, press Windows key + Ctrl + Shift + B to restart video driver. You will hear a beep indicating a response. You can press Windows key + P four times to switch between four different display modes to see if the black screen disappears. Disable all automatic applications and reboot. Reinstall or roll back device drivers and graphics driver. Reboot. Distended capacitors Over time, the capacitors on the motherboard may become overstressed or overheated. When this happens, they may swell, bulge, or leak fluid. Distended capacitors usually fail at some point, causing the motherboard to fail. For example, if you hear the fans in the power supply spin when you power on a system, but the motherboard itself doesn’t start, it is possible that capacitors on the motherboard have become distended. If this happens, inspect the motherboard and look for capacitors that are swollen on top or leaking brown liquid. While it is possible to carefully replace a failed capacitor on the motherboard, it is usually faster and more cost-effective to replace the entire motherboard. Lack of Power Power supplies wear out over time, especially if they’re overheated or overstressed. If the power supply can’t provide adequate amounts of electricity to the system, the computer may exhibit one of several behaviors: Unexpectedly shut down Continuously reboot itself Not power on The computer Power-On Self Test (POST) checks a computer’s internal hardware for compatibility and connection before starting the remainder of the boot process. If the computer passes the POST, it may give a single beep (some computers may beep twice) as it starts and continues to boot. Be aware that: Pin 8 wire on the power supply connector connects to the power good wire on the motherboard. If power disappears off that wire, the motherboard shuts down. If power quickly reappears on that wire, the system may attempt to come back on by itself, resulting in continual reboots. If power does not reappear on this wire, then the system will shut off. A failing power supply may not provide enough voltage on the pin 8 wire for the system to initially boot up. If you observe these symptoms, test the power supply to determine if it’s the source of the problem. Turn on the power supply. Test the voltage supplied on either a motherboard connector or on a hard disk connector. If the voltage is less than expected, the power supply may be at fault. For example, if a 12-volt wire is carrying less than 11 volts, the power supply is probably failing. If you determine the power supply is failing or has failed, do the following: Purchase a new power supply. Remove the old power supply from the system Mount the new power supply. Connect the new power supply to the motherboard and to all other internal devices. Power the system on and verify that the symptoms have been eliminated. Software Symptoms The following table discusses common symptoms attributable to software Symptom Description Boot errors A malfunctioning motherboard may generate error codes when the system is powered on. Every time the PC boots, it runs a power on self-test (POST) to make sure the basic hardware in the system is present and functioning correctly. If a problem is identified during POST, an error is generated. How the error message is reported depends on the motherboard manufacturer. The following are commonly used: Audible beeps Numeric codes Error messages The codes and messages vary by manufacturer. Check the motherboard documentation for specific details. The same error code may be used by a different manufacturer to indicate a different problem. Sometimes, a computer system may experience problems (such as a malfunctioning video adapter) that can prevent error messages from being displayed during POST. If this is the case, use a POST card to access POST error codes. Most models use an LED display to report error codes generated during POST. A POST card is often implemented as an expansion board that is inserted into an expansion slot in the motherboard. However, some POST cards also include a USB interface that allows the card to be connected to computers (such as notebook systems) that don’t have expansion slots. Intermittent device failure The black screen of death (BSoD) is a proprietary crash screen officially known as a stop error or black screen error. The BSoD displays when the Windows OS encounters a fatal system error. This was previously known as the blue screen of death. The Mac OS has a similar version called the spinning pinwheel of death (SPoD). Keep in mind: BSoD is a warning screen that is displayed to avert a system crash and avoid damage. A BSoD error freezes Windows and requires that the system be rebooted in order to continue to operate. BSoD errors relate to system hardware, temperature, timing, resources, corrupt registries, or viruses. The blue screen has become less common because operating systems are able to deal with errors without interruption. Intermittent device failure occurs when a component occasionally stops working. This usually indicates that the device itself is failing. The best remedy is to replace the failing device because it will fail completely at some point. Immediate replacement prevents the device from completely failing. Intermittent device failures may also be caused by device drivers that aren’t functioning properly. Device drivers are software and may contain coding errors. Before replacing a device experiencing intermittent failures, first verify that the latest drivers for that device are loaded. Sometimes downloading the latest driver and installing it will solve the problem. If updating the device driver doesn’t solve the issue, then you may need to replace the device. Missing BIOS/UEFI settings A constant source of power is required to store the settings configured in the motherboard BIOS/UEFI chipset. The motherboard also needs constant power to keep the system clock running while the system is powered off. Most motherboards implement a small battery that provides this power. If this battery starts to fail, the following may occur when the system is powered on: The system clock loses time. Settings configured in BIOS/UEFI are lost. If this happens, it’s likely that the motherboard battery has failed and needs to be replaced. Sensory Symptoms The following table discusses common sensory symptoms. Symptom Description Buzzing or grinding noise A common problem is a PC fan making a buzzing, humming, or clicking noise. There are many things that can cause the fan to make a grinding noise but the most likely ones are: Dust buildup. Loose screws or bad mounting holds for fans. Uneven case surface can cause fan blade and motor noise. Certain RPM ranges can cause certain fan motors to create noise. The internal cable is too near the fan. Bearings or motors inside are defective or failing. Another noise may be caused by a failing hard drive. This may start as a clicking or low-pitched buzzing noise and evolve to grinding. Do not ignore this noise. You can suspect a failing disk drive is the source of the noise if the computer also exhibits: Sluggish performance or freezes. Frequent error messages while running software. Application crashes. Disk errors. Strange behavior. Immediately back up computer data if you suspect the hard disk is failing. After backing up data, replace the hard disk as soon as possible. Overheating Internal system components within a computer generate a great deal of heat that must be dissipated. Overheating causes premature component failure. Overheating could be caused by several conditions: Inadequate air flow. This may be the result of an inadequate number of fans in the system or fans that are too small. In this situation, you can add fans to the system to increase air flow. Improperly installed fans. Fans must be oriented to force air through the system in the same direction. Otherwise, they may fight against each other and prevent air from flowing properly. Failing fans. A failing fan moves less air than a properly functioning fan. It’s not uncommon for a failing fan to generate a screeching noise that is caused by worn parts within the fan assembly. The solution is to replace the failing fan. Dust buildup. Excessive dust within the system can block air flow and cause overheating. Use compressed air or an anti-static vacuum to remove dust buildup. Environmental heat. If the air temperature outside the computer is overly warm, the temperature inside the system will be overly warm. Implement a properly balanced HVAC system in the work area to remove excess heat from the environment. Monitor the internal temperature of computer systems. Most motherboards include several sensors you can use to monitor the system temperature. Usually you can view the current temperature within the BIOS/UEFI setup. There are software applications available that can read the current temperature values from the sensors and display them on screen. Unlike using a BIOS/UEFI monitoring utility, these tools allow you to monitor the temperature dynamically while the system is in use. Most motherboards include a thermal shutdown feature. When the system temperature reaches the maximum threshold, the thermal shutdown feature immediately shuts the computer down to prevent component damage. However, it typically does not shut the system down cleanly, so there is a risk of data corruption when this happens. Smoke or burning smell If you observe smoke or a burning smell coming from a computer, it indicates that electricity is not flowing in the correct manner within the system. If smoke is observed, shut the system off immediately. This issue could be caused by: A connector that isn’t seated properly and electricity is arcing between leads. A short circuit in the printed circuit board of the motherboard or on an expansion board. An improperly installed component. Unfortunately, a component that is smoking is probably damaged to some degree. It’s unlikely that it will ever function properly again. You usually must replace the component.