CompTIA Chapter 6 & 7 - Motherboards PDF

Chapter 6 Motherboards **How Motherboards Work** **Three variable and interrelated characteristics define modern motherboards:** - **The Form factor**: determines the physical size of the motherboard as well as the general location of components and ports. - The **chipset:** defines the...

Chapter 6 Motherboards **How Motherboards Work** **Three variable and interrelated characteristics define modern motherboards:** - **The Form factor**: determines the physical size of the motherboard as well as the general location of components and ports. - The **chipset:** defines the type of processor and RAM the motherboard requires and determines to a degree the built-in devices the motherboard supports, including the expansion slots. - **built-in** components determine the core functionality of the system. **Form Factors** Motherboard form factors are industry-standardized shapes and layouts that enable motherboards to work with cases and power supplies. A single form factor applies to all three components. **ATX Form Factor** most common form factor improvements over AT: - The position of the power supply creates better air movement. The CPU and RAM are placed to provide easier access, and the rearrangement of components prevents long expansion cards from colliding with the CPU or northbridge. - Placing the RAM closer to the northbridge and CPU than on AT boards, offer users enhanced performance as well. The shorter the wires, the easier to shield them and make them capable of handling double or quadruple the clock speed of the motherboard. - ATX motherboards come in three variations to accommodate different types of cases. - The **ATX** form factor. - The **microATX** yet the standard ATX connections. motherboard fits into a standard ATX case or in the much smaller microATX cases. - **ITX** VIA created smaller form factors that today populate the SFF market, specifically **Mini-ITX. Mini-ITX**) competes head-to-head with the virtually identical picroATX. ITX power supplies are quite small compared to a typical power supply. Lower power usage produces less heat, thus enabling passive cooling on many SFF systems. The lack of fan noise makes them ideal for media center PCs. **From Factors:** **ATX: 12" by 9.6" inches.** **MicroATX: 9.6" Square.** **Mini-ITX: 6.7" Square.** **Nano-ITZX: 4.7" Square.** **Pico-ITX: 3.9" \* 2.8" Rectangle.** **Chipset** **The chipset determines:** - The type of processor the motherboard accepts. - The type and capacity of RAM. - The sort of internal and external devices that the motherboard supports. The primary expansion bus communication goes through the CPU as well, something the southbridge handled back in the day. Most techs refer to the remaining support chips on the motherboard as the chipset, although the terms northbridge and southbridge are dead. The chipset defines almost every motherboard feature short of the CPU itself. Most motherboards have **headers---internal connectors**---to plug in header cables for additional external ports. These headers are standardized, so many cases have built-in front USB ports that have header cables attached. **Structure and Function of the Expansion Bus** Every device in the computer connects to the external data bus and the address bus including hee expansion slots.. They connect to the rest of the PC through the chipset. Exactly where on the chipset varies depending on the system. On newer systems, the expansion slots connect to the CPU because modern CPUs contain a lot of controller features that used to be in the chipset. The chipset provides an extension of the address bus and data bus to the expansion slots, and thus to any expansion cards in those slots. If you plug a hard drive controller card into an expansion slot, it functions just as if it were built into the motherboard, but dose not run at the same speed as devices that are connected to the motherboard because of the system crystal. **PCI (Peripheral Component Interconnect**) is a standard for connecting peripheral devices to a computer\'s motherboard. It was widely used in the 1990s and early 2000s, providing a fast and efficient way for hardware components to communicate with the CPU and memory. 1. **Data Transfer Rates:** - Original PCI standard supports data transfer rates of up to 133 MB/s, with 32 or 64-bit data widths. **PCI Express (PCIe) Peripheral Component Interconnect Express**) is a high-speed interface standard used to connect peripheral devices to a computer\'s motherboard. It is the successor to older standards like PCI and AGP, providing significant improvements in speed, scalability, and versatility. **Key Features of PCI Express:** 1. **Serial Bus Architecture:** - Unlike the parallel architecture of PCI, PCIe uses a serial interface, where data is transmitted over pairs of lanes. Each lane consists of two pairs of wires, one for transmitting data and one for receiving. 2. **High Data Transfer Rates:** - PCIe significantly increases data transfer rates compared to PCI. Each PCIe 4.0 lane supports data rates of around 2 GB/s, with PCIe 5.0 doubling this rate to 4 GB/s per lane. 3. **Lane Scalability:** - Devices can use multiple lanes (x1, x4, x8, x16, etc.) to increase bandwidth. For example, most modern GPUs use a PCIe x16 slot to leverage the maximum available bandwidth. 4. **Point-to-Point Connections:** - PCIe provides dedicated, direct point-to-point connections between the motherboard and the device, eliminating bottlenecks associated with shared bus architectures. 5. **Backward Compatibility:** - PCIe maintains backward compatibility with older versions, allowing newer motherboards to work with older PCIe devices, albeit at the lower performance of the older standard. **Advantages of PCI Express:** 1. **Increased Bandwidth:** - Offers significantly higher bandwidth than PCI, enabling faster communication between the CPU and peripheral devices, which is essential for high-performance applications. 2. **Versatility and Flexibility:** - Supports a wide range of devices, from graphics cards and SSDs to network interface cards and Wi-Fi adapters. 3. **Hot-Plugging:** - Some PCIe devices support hot-plugging, allowing them to be added or removed without shutting down the system, which is beneficial for servers and high-availability systems. - **Shared Lanes:** Some motherboards lack enough lanes for all slots to run at maximum capacity simultaneously, which can slow down other devices when expansion cards are added. - **PCIe Up-Plugging:** Up-plugging allows you to use a smaller PCIe card (e.g., x8) in a larger PCIe slot (e.g., x16) on a motherboard that supports this feature. Even though the card fits into the larger x16 slot, it will operate at its native lane capacity, running at x8 speed. 4. **Energy Efficiency:** - PCIe includes advanced power management features, allowing devices to reduce power consumption when full bandwidth is not needed. - **Wiring Mismatch:** A slot might be wired for fewer lanes than its size indicates. For example, a ×16 slot could be wired for only 4 or 8 lanes. A video card expecting 16 lanes in such a slot will operate at reduced capacity. - The most common PCIe slot is the 16-lane (×16) version, frequently used for video cards. PCIe is designed to be compatible with other expansion slots, even different types of PCI. - The bandwidth provided by a ×16 PCIe slot exceeds the needs of most devices except video cards. Therefore, most PCIe motherboards also include slots with fewer lanes, with ×1 being the most common general-purpose slot and ×4 slots appearing on some boards. - **PCIe Version Discrepancy:** Older PCIe versions have lower bandwidth, and motherboards might support different versions for different slots. The CPU can also affect the effective PCIe version. - **Multi-Purpose Lanes:** PCIe lanes can be used for other functions on the board, affecting speed and functionality based on the number of slots/lanes in use. - **PCIe 1.0 to 5.0:** Over time, PCIe has evolved through several versions, each offering increased bandwidth and improved features. PCIe 6.0, set for wider adoption, is expected to further double the data rate per lane compared to PCIe 5.0. - **Mini PCIe and M.2:** Variants of PCIe, like Mini PCIe and M.2, have been developed for smaller devices, providing the same benefits of speed and scalability in more compact form factors. **Each direction of a lane runs at 2.5 giga transfers per second (GTps):** - PCIe 1.x, 5 GTps - PCIe 2.x, 8 GTps - PCIe 3.x,16 GTps - PCIe 4.0! Better yet,  \- **Unsigned Drivers** In **Windows Hardware Compatibility Program,** the drivers get a digital signature that says Microsoft tested them and found all was well. Some older versions of Windows had support for unsigned drivers automatically enabled. These are drivers that have not gone through the Windows Hardware Compatibility Program, so their software does not have a digital signature from Microsoft. Modern versions of Windows (10 and 11) can support unsigned drivers, but this is disabled by default. **Driver Rollback** All versions of Windows allow of rolling back to previous drivers after an installation or driver upgrade. To access the rollback feature, simply open Device Manager and access the properties for the device you want to adjust. On the Driver tab. **Beta Drivers** are fine for the most part, but they can sometimes cause amazing system instability---never a good thing! If you use beta drivers, make sure you know how to uninstall or roll back to previous drivers. **Troubleshooting Expansion Cards** **Device Manager** provides the first diagnostic and troubleshooting tool in Windows. After you install a new device, Device Manager gives you many clues if something has gone wrong. Occasionally, Device Manager may not even show the new device. If that happens, verify that you inserted the device properly and, if needed, that the device has power. Run the Add Hardware Wizard and see if Windows recognizes the device. In Windows, you run the program by clicking Start and typing the name of the executable in the Search bar: **hdwwiz.exe**. If Device Manager doesn\'t recognize your device, it could either be physically damaged and need replacing, or it\'s an onboard device that\'s turned off in CMOS. Device Manager typically detects devices, but problems often show up as error icons: - A black \"!\" on a yellow triangle means the device is missing, not recognized by Windows, or has a driver issue, although it may still function. - A black downward-pointing arrow on a white background indicates a disabled device, either manually turned off or damaged, and it will not operate. - **The "!" symbol is the most common error symbol and usually the easiest to fix:** - First: double-check the device's connections. - Second, try reinstalling the driver with the Update Driver button. To get to the Update Driver button, right-click the desired device in Device Manager and select Update driver to open the updating wizard. **If you get a downward-pointing arrow**: - First check that the device isn't disabled. Right-click the device and select Enable. If that doesn't work (it often does not), try rolling back the driver (if you updated the driver) or uninstalling (if it's a new install). - Shut the system down and make triple-sure you have the card physically installed. Then redo the entire driver installation procedure, making sure you have the most current driver for that device. - If none of these procedures works, return the card---it's almost certainly bad. you can usually find a copy of the manual on the manufacturer's Web site. Make sure you match the revision number of the motherboard as well as the model number. **CAUTION:** Pay attention to the location of the standoffs if you're swapping a motherboard. If you leave a screw-type standoff beneath a spot on the motherboard where you can't add a screw and then apply power to the motherboard, you run the risk of frying the motherboard. **Troubleshooting Motherboards** Motherboards fail. Not often, but motherboards and motherboard components can die from many causes. **Symptoms** **Motherboard failures can generally be categorized into three types:** **1. Catastrophic Failures: These are complete failures where the computer won\'t boot at all. This might be preceded by a loud pop or a burning smell, often due to a blown capacitor or another component failure. If no indicator lights are active, it could be a motherboard or power supply failure. Such failures can result from manufacturing defects, termed burn-in failures, or from electrostatic discharge (ESD). Burn-in failures are uncommon and typically occur within the first 30 days of use, requiring a motherboard replacement.** **2. Component Failures: These involve specific faulty parts on the motherboard, leading to sporadic problems or unstable connections with devices. A device might show in the BIOS but not work correctly in the operating system, like a hard drive on a faulty controller or a USB port that ceased functioning after an electrical storm. These issues are typically rare.** **3. Ethereal Failures: The most challenging to diagnose, these are intermittent issues that make the system behave unpredictably, such as random reboots or blue screens of death (BSoD) during intensive tasks. These issues are sporadic and do not follow a consistent pattern, making them difficult to identify and troubleshoot.** **Recognizing the type of motherboard failure can guide you in troubleshooting and deciding on the next steps, such as inspecting individual components or replacing the motherboard.** **SIM**: Check out the Chapter 6 Challenge! sim, "Label Motherboard," over at https://www.totalsem.com/110x. It'll help you remember all the motherboard components in case you get a performance-based challenge on the CompTIA A+ 1101 exam. **Techniques** Troubleshooting a potential motherboard failure effectively involves a systematic approach to isolate the problem: 1\. **Test Different Components:** Swap out drives or other components to see if the issue persists. This can help verify whether a drive or device is functioning correctly or if the problem lies with the motherboard. 2\. **Use POST Cards**: Employ a modern POST card with a diagnostic screen to perform hardware tests. POST cards can be found for both PCI and PCIe slots and even USB, which are useful for diagnosing portable computers. 3\. **Isolate the Issue:** The goal is to identify the problem by ruling out potential causes. This structured method applies to both simple issues and more complex motherboard problems. 4\. **Document Your Process:** Keep detailed notes of the tests and changes made. Documenting your troubleshooting steps prevents redundant efforts and can help identify patterns in the issues. Recreating crashes through specific actions can provide insights into the root cause. **CAUTION:** If you've lost components because of ESD or a power surge, you would most likely be better off replacing the motherboard. The damage you can't see can definitely sneak up to bite you and create system instability. If you have a component failure, you can often replace the component with an add-on card that will be as good as or better than the failed device.  If your component failure is more a technology issue than physical damage, you can try upgrading the BIOS on the motherboard. You can quite readily upgrade this programming by flashing the BIOS: running a small command-line program to write a new BIOS in the flash ROM chip. Finally, if you have an ethereal, ghost-in-the-machine type of problem that you have finally determined to be motherboard related, you have only a couple of options for fixing the problem. You can flash the BIOS in a desperate attempt to correct whatever it is, which sometimes does work and is less expensive than the other option, which is replacing the motherboard. Chapter 7 Power Supplies **Supplying AC** Power supply standard IEC-320 connector on the other. - In the United States, standard AC is between input 110 and 120 V, often written as \~115 VAC (volts of alternating current). - Most of the rest of the world uses230 VAC, Modern power supplies are designed to support both voltages, aka **dual voltage**. Not only are they dual voltage, but they're also autosensing. Just plug in the power supply and it automatically adjusts to whatever voltage is offered. **Testing Your Power Source** Before you plug any critical components into an AC outlet, take a moment to test the outlet first by using a multimeter or a device designed exclusively to test outlets. Failure to test AC outlets properly can result in inoperable or destroyed equipment, as well as possible electrocution. **The IEC-320 plug has three holes:** - hot wire: carries electrical voltage. - neutral wire: carries no voltage, but instead, complete the circuit by returning electricity to the local source, normally a breaker panel. - Ground wire: makes it possible for excess electricity to return safely to the ground, a short-circuit condition. **When testing AC power, you want to check for three things:** - The hot outputs approximately 115 V (or whatever the proper voltage is for your part of the world). - That the neutral connects to ground (0 V output). - The ground connects to ground (again, 0 V). You can use a multimeter---often also referred to as a **volt-ohm meter (VOM) or digital multimeter (DMM)**---to measure several aspects of electrical current. A multimeter consists of two probes, an analog or digital meter, and a dial to set the type of test you want to perform. Note that some multimeters use symbols rather than letters to describe AC and DC settings. - V with the solid line above = direct current. - V\~ stands for alternating current. **You need to make sure that three things match before you plug an AC adapter into** **a device:** - Voltage -If either the voltage or amperage output is too low, the device won't run. - Amperage -If either the voltage or amperage---especially the former---is too high, on the other hand, you can very quickly toast your device. Don't do it! - Polarity -If the polarity is reversed, it won't work, just like putting a battery in a flashlight backward. Always check the voltage, amperage, and polarity of a replacement AC adapter before you plug it into a device. **Most multimeters offer at least four types of electrical tests:** Continuity, resistance, AC voltage (VAC), and DC voltage (VDC) are key concepts in electrical testing. Continuity tests determine if electrons can flow through a wire, indicating an intact path. This can help check if a fuse is good or identify breaks in wires. If a multimeter lacks a continuity tester, use the resistance setting---where a broken wire shows infinite resistance, and a good one shows little to none. Testing AC and DC voltages involves ensuring measured values meet expected parameters.  No matter how clean the AC supply appears to a multimeter, voltage from the power company tends to drop well below (sag) and shoot far above (power surge or spike) the standard 115 V (in the United States). These sags and spikes usually don't affect lamps and refrigerators in such scenarios, but they can keep your PC from running or can even destroy a PC or peripheral device. **Two essential devices handle spikes and sags in the supply of AC:** - **Surge Suppressors** Surges or spikes can damage computer components, while sags usually just cause shutdowns or reboots. To protect against surges, use a surge suppressor rated for UL LCC 1449 at 330 volts, ensuring substantial protection. \[UL\](https://www.ul.com) is a trusted U.S.-based testing laboratory setting important standards for electronics safety. **Check the joules rating before buying a new surge suppressor:** - **joule** is a unit of electrical energy a surge suppressor can handle before it fails. - Surge suppressor should rate at a minimum of 2000 joules, the more joules, the better the protection. Don't forget that surges also come from telephone and cable connections. Anything with copper cables---cable modems, or even an old DSL modem---make sure to get a surge suppressor that includes support for these types of connections. Many manufacturers make surge suppressors with telephone line protection. No surge suppressor works forever. Make sure your surge suppressor has a test/reset button so you'll know when the device has died. **EXAM TIP:** Large sags in electricity are also known as **brownouts.** When the power cuts out completely, it's called a **blackout,** Under-voltage event or complete power failure can damage electronic devices and computers**.** Your power lines take in all kinds of strange signals that have no business being in there, such as electromagnetic interference (EMI) and radio frequency interference (RFI). All better surge suppressors add power conditioning to filter out EMI and RFI. Uninterruptible Power Supplies (UPS) are measured in both watts and volt-amps (VA). Watts represent the actual power supplied during an outage, whereas VA refers to the power the UPS could provide under perfect conditions. While UPS units deliver AC power smoothly at 60 Hz (or 50 Hz in some regions), connected devices like power supplies and monitors may not utilize all available power efficiently. If devices used the full power constantly as the AC current alternates, VA would equal watts. The watts value they give is a guess, and it's never as high as the VAs. The VA rating is always higher than the wattage rating. Because you have no way to calculate the exact efficiency of every device you'll plug into the UPS, go with the wattage rating. You add up the total wattage of every component in your PC and buy a UPS with a higher wattage. Remember that the UPS is a battery with a limited amount of power, so you then need to figure out how long you want the UPS to run when you lose power. My personal favorite is on the APC by Schneider Electric Web site: https://www.apc.com (type **UPS selector** in the search field). APC makes great surge suppressors and UPSs, and the company's online calculator will show you the true wattage you need---and teach you about whatever new thing is happening in power at the same time. Every UPS also has surge suppression and power conditioning: - look for the joule and UL 1449 ratings. - look for replacement battery cost - look for a UPS with a USB or Ethernet (RJ-45) connection. These handy UPSs come with monitoring and maintenance software that tells you the status of your system and the amount of battery power available, logs power events, and provides other handy options. **Supplying DC** converting public utility voltage AC (115/120 V in the United States, 230 V in many other countries) into several DC voltages (notably, 3.3 V, 5 V, and 12 V) usable by the delicate interior components. most common size by far is the standard 150 mm × 140 mm × 86 mm desktop. The PC uses the 12-V current to power motors on devices such as hard drives and optical drives, and it uses the 3.3- and 5-V current for support of onboard electronics. Manufacturers may use these voltages any way they wish. **Power to the Motherboard** Modern motherboards use a 20- or 24-pin P1 power connector. Some motherboards may require special 4-, 6-, or 8-pin connectors to supply extra power.  **Power to Peripherals: Molex, Mini, and SATA** **Molex Connectors** Molex connector supplies 5-V and 12-V current for fans and older drives. It has notches, called **chamfers**, that guide its installation. Molex connectors require a firm push to plug in properly, and a strong person can defeat the chamfers, plugging a Molex in upside down. Not a good thing. Always check for proper orientation before you push it in! **Mini Connectors** A few power supplies still support the mini connector or Berg connector. The mini supplies 5 V and 12 V to peripherals. Originally adopted as the standard connector on 3.5-inch floppy disk drives, you'll still see the occasional device needing this connector. **CAUTION** As with any power connector, plugging a mini connector into a device the wrong way will almost certainly destroy the device. Check twice before you plug one in! **SATA Power Connectors** - Serial ATA (SATA) drives need a 15-pin SATA power connector. - The larger pin count supports the SATA hot-swappable feature and 3.3-, 5-, and 12-V devices. - The 3.3-V pins are not used in any current iteration of SATA drives and are reserved for possible future use. - All three generations of SATA use the same power connectors. SATA power connectors are L shaped, making it almost impossible to insert one incorrectly into a SATA drive. - No other device on a computer uses the SATA power connector.  **Splitters and Adapters** You may occasionally find yourself without enough connectors to power all of the devices inside your PC. In this case, you can purchase splitters to create more connections. You might also run into the phenomenon of needing a SATA connector but having only a spare Molex. Because the voltages on the wires are the same, a simple adapter will take care of the problem nicely. Splitters have two negative effects on a coaxial cable. - They limit the distance the signal will travel. - They degrade the signal. **Rails** Generally, the PC's power comes from a single transformer that takes the AC current from a wall socket and converts it into DC current that is split into three primary DC voltage rails: 12 V, 5 V, and 3.3 V. Groups of wires run from each of these voltage rails to the various connectors. Each rail has a maximum amount of power it can supply. Normal computers use rarely approaches this feeling, but powerful computers with advanced processors and graphics cards require more power than some rails can provide. Today's power supply manufacturers produce single- and multi-rail high-amperage PSUs. **ATX12V 2.0** 1. **Introduction of the 24-Pin Main Connector:** - **The ATX12V 2.0 specification introduced a 24-pin main power connector, expanding from the previous 20-pin connector. This extra 4-pin configuration provides additional voltage lines to accommodate the increasing power demands of modern motherboards and peripherals, allowing for more stable voltage supply to critical components.** 2. **Dedicated 12V Rail:** - **ATX12V 2.0 introduced a stronger emphasis on the +12V rail (VDC), which supplies voltage primarily to the CPU and GPUs. This focus supports increased stability and voltage delivery efficiency, catering to the needs of more power-hungry components.** 3. **Increased Current for 12V Rail:** - **With version 2.0, the specification allows for increased current capacity on the +12V rail (VDC). This adjustment supports the higher voltage requirements of advanced processors and graphics cards, enabling better performance and reliability.** 4. **Efficiency and Cooling Improvements:** - **This version introduced efficiency standards to encourage the use of more efficient components and design improvements. These enhancements help reduce heat output and voltage wastage, directly impacting system reliability and performance.** 5. **Support for Legacy Systems:** - **Despite enhancements, ATX12V 2.0 maintained backward compatibility with older systems by typically providing adapters or maintaining support for legacy connectors, ensuring users could transition without needing immediate system-wide upgrades.** 6. **SATA Power Connectors:** - **With the rise of SATA devices, ATX12V 2.0 power supplies began to include SATA power connectors as standard. The SATA connectors provide 3.3V, 5V, and 12V (VDC), essential for modern storage devices.** 7. **Enhanced Power Distribution:** - **Improved voltage distribution across various lines supports a broader range of hardware configurations without excessive load on any single rail or component, ensuring adequate voltage delivery to different components even under high-demand scenarios.** **Voltage Supply Ratings in ATX12V 2.0** - **+12V Rail (VDC): Critical for supplying voltage to the CPU, GPUs, and other high-power components. Typically provides the bulk of the voltage needed, often rated at a higher current to support the entire system\'s load.** - **+5V Rail (VDC): Used primarily for legacy components and some modern peripherals. Although its usage has decreased, it still supports various motherboard functions and older drive systems.** - **+3.3V Rail (VDC): Supports chips on the motherboard and similar devices. Like the 5V rail, it helps power smaller, less demanding components and contributes to overall system stability.** - **-12V Rail (VDC): This rail is less common in modern systems but can be present for backward compatibility, providing minimal voltage primarily for older standards and specific circuitry requirements.** **Importance of ATX12V 2.0** - **Versatility: Supports a wide range of modern and older hardware, making it a flexible choice for various system builds.** - **Stability: Better voltage rail distribution helps stabilize systems, minimizing voltage-related failures, which is crucial for gaming, high-performance tasks, and professional applications.** - **Future-Proofing: Designed to meet the needs of evolving technologies by providing more connectors and supporting greater voltage loads.** **Considerations When Choosing an ATX12V 2.0 Power Supply** - **Wattage Rating: Ensure the power supply provides enough wattage to cover your entire system, including any planned upgrades, typically ranging from 300W for basic setups to 1000W or more for high-performance rigs.** - **Efficiency Rating: Look for an 80 Plus certification or higher, which indicates good energy efficiency and can reduce long-term energy costs and heat output.** - **Number of Connectors: Ensure the power supply has sufficient connectors, including PCIe, SATA, and others matching your component needs.** - **Quality and Brand: Choose reputable brands known for reliability and quality to ensure a stable voltage source for your system.**  The 8-pin EPS12V connector, also known as EATX12V or ATX12V 2x4, is used on ATX motherboards to supply power to high-end CPUs that require significant amounts of power. This connector can often split into two 4-pin sets for compatibility with older motherboards needing only a 4-pin (P4) connector. **Key Features of the 8-pin EPS12V Connector:** 1. **Power Supply to CPU:** - The 8-pin EPS12V connector provides additional power to the CPU, supplementing what the 24-pin ATX connector supplies. 2. **Increased Power Capacity:** - Compared to the older 4-pin ATX12V connector, the 8-pin connector provides double the power, accommodating high-performance CPUs that require more power, especially under heavy loads or when overclocking. 3. **Connector Design:** - The plug consists of two rows of four pins (4+4 configuration), allowing for compatibility with motherboards requiring either a 4-pin or 8-pin connection. - They are keyed to prevent incorrect connections. 4. **Power Delivery:** - Typical maximum power delivery is around 336 watts, depending on the power supply unit (PSU) specifications. - This ensures stable power to high-demand CPUs. 5. **Backward Compatibility:** - Many PSUs come with a \"4+4 pin\" connector that splits into two 4-pin segments, allowing for flexibility in attaching to either 4-pin or 8-pin CPU power slots. **Considerations for Using the 8-pin EPS12V Connector:** - **Mandatory for High-Power Systems:** - If your system features high-end CPUs or is overclocked, connecting the 8-pin connector is essential for stability and performance. - **Power Supply Compatibility:** - Ensure your PSU has an 8-pin (or compatible 4+4 pin) CPU power connector before building a high-power system. - **Installation:** - When installing, make sure the connector is firmly connected to avoid power issues. - Double-check that the PSU can handle the additional load, especially if multiple power-hungry components are installed. - **Additional Power Connectors:** - Some motherboards designed for extreme overclocking may have additional CPU power connectors (such as an extra 4-pin or another 8-pin EPS). The **8-pin PCI Express (PCIe)** power connector is used to provide additional power to graphics cards and other PCIe devices that require more power than the PCIe slot on the motherboard can supply. Here\'s a detailed look at the 8-pin PCIe connector: **Key Features of the 8-pin PCIe Power Connector:** 1. **Supplemental Power:** - While the PCIe slot itself provides up to 75 watts, high-performance graphics cards often require more power, which is supplied through additional connectors like the 8-pin PCIe power connector. 2. **Power Capacity:** - An 8-pin PCIe connector can deliver up to 150 watts of additional power to the graphics card. - It\'s often used in combination with other connectors (e.g., 6-pin PCIe) to meet the total power demand of modern GPUs. 3. **Connector Design:** - The 8-pin PCIe connector is slightly different from the 8-pin EPS12V connector, though they appear similar. They are keyed differently to prevent incorrect connections. - Typically, PSU connectors for PCIe power may be labeled or color-coded to avoid confusion. 4. **6+2 Configuration:** - Many PSUs provide a \"6+2 pin\" connector design to support both 6-pin and 8-pin configurations, offering flexibility depending on the GPU\'s requirements. **Using the 8-pin PCIe Power Connector:** - **Check GPU Requirements:** - Review the power requirements of your GPU to determine how many and which type of connectors are needed. - Ensure that the power supply units can provide the necessary connectors and sufficient power capacity. - **Installation:** - Connectors should be firmly inserted into the GPU\'s power sockets. - Make sure the connectors are not confusingly mixed with CPU power connectors (EPS). - **Power Supply Compatibility:** - Verify that your power supply supports the total wattage required by your GPU and other components. - Consider efficiency ratings (e.g., 80 PLUS) to ensure your PSU operates efficiently under load. - **Consider Dual Connectors:** - High-end graphics cards may require more than one 8-pin or multiple power connectors (e.g., a combination of 8-pin and 6-pin). **Over-Current Protection (OCP)** is a crucial safety feature implemented in electronic devices, particularly in power supplies, to prevent damage caused by excessive current. Here's an overview of OCP, its functionality, and its importance: What is OCP? - **Definition:** OCP is a protective mechanism that automatically shuts down or limits the output current of a power supply when it exceeds a predetermined threshold. - **Purpose:** The primary goal of OCP is to safeguard both the power supply and the connected components from damage caused by excessive current that can lead to overheating, fire hazards, or component failure. **How OCP Works:** 1. **Detection:** - The power supply continuously monitors the output current levels. If the current exceeds the designated limit, the OCP circuit activates. 2. **Response Mechanism:** - **Depending on its design, OCP can either:** - Shutdown Mode: Completely cut off power to prevent damage. - Current Limiting: Reduce the current output to a safe level while maintaining power delivery. 3. **Automatic Recovery:** - After the fault condition is resolved (like disconnecting the overloaded component), many power supplies automatically reset and resume normal operation. **Importance of OCP:** 1. **Safety:** - OCP prevents electrical fires and damage to devices, ensuring safe operation even under extreme conditions. 2. **Component Protection:** - Protects connected devices (like GPUs, CPUs, and HDDs) from being subjected to harmful levels of current, which can lead to shortened lifespans or immediate failure. 3. **Reliability:** - Power supply units with OCP typically exhibit increased reliability and durability, making them a preferred choice in critical systems. 4. **Compliance:** - Adhering to safety standards often requires OCP, which can be important for regulatory compliance in many regions. **Design Considerations:** - **Threshold Settings:** - Manufacturers set OCP thresholds based on the expected load capacities of the power supply and its intended usage. - **Testing:** - OCP needs thorough testing to ensure it responds appropriately to faults without causing nuisance tripping or unnecessary shutdowns.  **SIM** Check out the Chapter 7 Challenge! sim, "ID PSU Connector," over at https://www.totalsem.com/110X. It'll help you identify and memorize the standard power supply connectors. **Niche-Market Power Supply Form Factors** The demand for smaller and quieter PCs led to the development of niche-market power supply form factors. All use standard ATX connectors but differ in size and shape from standard ATX power supplies. - **Mini-ITX** and **microATX** Smaller power supply form factors designed specifically for mini-TX and microATX cases. - **TFX12V** A small power supply form factor optimized for low-profile ATX systems. - **SFX12V** A small power supply form factor optimized for systems using FlexATX motherboards. **Active PFC** Harmonics cause the humming sound from electrical components and can damage equipment over time, affecting power supplies and other devices in the circuit. In areas with many PCs, harmonics may even damage the power supplier\'s equipment. Quality PC power supplies use active power factor correction (active PFC) to smooth incoming power, eliminating harmonics. It\'s important to buy power supplies with active PFC, as this feature will usually be clearly stated on the packaging. **Wattage Requirements** Power supplies can\'t convert 100% of AC power to DC, losing some energy as heat. Efficiency is advertised, with ATX12V 2.0 standards requiring at least 70% efficiency, though many offer over 80%. **Calculating Power Needs** Open a Web browser and check out the Outer Vision Power Supply Calculator at [[https://outervision.com/power-supply-calculator.]](https://outervision.com/power-supply-calculator) Enter the details on your desired systems and let this amazing tool do the math for you. **Troubleshooting Power Supplies** Power supplies fail in two ways: sudden death and slowly over time. When they die suddenly, the computer will not start and the fan in the power supply will not turn. In this case, verify that electricity is getting to the power supply before you do anything. If the system has electricity, the best way to verify that a power supply is working or not working is to use a multimeter to check the voltages coming out of the power supply. **No Motherboard** Power supplies will not start unless they're connected to a motherboard, so what do you do if you don't have a motherboard you trust to test? First, try an ATX tester. Look for one that supports both 20- and 24-pin motherboard connectors as well as all of the other connectors on your power supply.  **When Power Supplies Die Slowly** Unfortunately, the majority of PC problems occur when power supplies die slowly over time. This means that one of the internal electronics of the power supply has begun to fail. The failures are always intermittent and tend to cause some of the most difficult to diagnose problems in PC repair. The secret to discovering that a power supply is dying lies in one word: intermittent. Whenever you experience intermittent problems, your first guess should be that the power supply is bad. Here are some other clues you may hear from users: - "Whenever I start my computer in the morning, it starts to boot, and then locks up. If I press ctrl-alt-del two or three times, it will boot up fine." - "Sometimes when I start my PC, I get an error code. If I reboot, it goes away. Sometimes I get different errors." - "My computer will run fine for an hour or so. Then it locks up, sometimes once or twice an hour." - "It takes a couple of tries---plugging and unplugging---with a new USB device before my system recognizes it." Sometimes something bad happens and sometimes it does not. That's the clue for replacing the power supply. And don't bother with the multimeter; the voltages will show up within tolerances, but only once in a while they will spike and sag (far more quickly than your multimeter can measure) and cause these intermittent errors. If in doubt, change the power supply. Power supplies break in computers more often than any other part of the PC except components with moving parts. You might choose to keep extra power supplies on hand for swapping and testing. Every computer workbench needs a fire extinguisher, but make sure you have the right one. The fire prevention industry has divided fire extinguishers into five fire classes: - **Class A** Ordinary free-burning combustible, such as wood or paper - **Class B** Flammable liquids, such as gasoline, solvents, or paint - **Class C** Live electrical equipment - **Class D** Combustible metals such as titanium or magnesium - **Class K** Cooking oils, trans-fats, or fats Only a Class C fire extinguisher on a burning computing device. All fire extinguishers are required to have their type labeled prominently on them. Many fire extinguishers are multiclass in that they can handle more than one type of fire. The most common fire extinguisher is type ABC---it works on all common types of fires, though it can leave residue on computing equipment. **Redundant Power Supplies** Redundant power supplies are power supply systems designed to provide uninterrupted electrical power to critical systems like servers, network switches, and enterprise storage devices. These systems are essential in environments where consistent power availability is critical to prevent downtime, data loss, or damage to hardware. How Redundant Power Supplies Work 1. **Configuration**: - Redundant power supplies are typically configured as dual or multiple units within the same device. Each power supply unit (PSU) operates independently but in parallel to ensure continuous power delivery. 2. **Failover Capability**: - In normal operation, both (or all) power supplies share the load. If one power supply fails, the other power supply automatically takes over the full load without interrupting power to the device. This is known as hot-swapping, where the failed unit can be replaced without shutting down the system. 3. **Load Balancing**: - Redundant systems often balance the power load between units during normal operations. This helps prolong the life of each power supply by reducing the stress on individual units. 4. **Hot-Swappable**: - Redundant power supplies are hot-swappable, meaning they can be replaced without powering down the equipment. This feature is crucial for maintaining uptime and reliability in mission-critical environments. Benefits of Redundant Power Supplies - **Increased Reliability**: - Redundant power supplies ensure that equipment remains operational even if one power supply unit fails. This reliability is crucial in data centers and other mission-critical environments. - **Enhanced System Uptime**: - By providing a backup power source, redundant power supplies help maintain system uptime, which is essential for servers, storage systems, and networking devices supporting critical operations. - **Maintenance Without Downtime**: - Enables maintenance and replacement of faulty power units without shutting down the device, allowing for servicing during normal operation hours. - **Load Sharing and Efficiency**: - Multiple power supplies can share the electrical load, which can improve the overall efficiency and lifespan of each power supply unit by reducing thermal stress.