Computer Systems (Hardware) PDF

Computer Systems (Hardware) * You have to refer to the official material in Moodle (slides + videos) and don’t only depend on this notebook. Good luck in your studies! PASS leader: Fatema Habib Special thanks for:...

Computer Systems (Hardware) * You have to refer to the official material in Moodle (slides + videos) and don’t only depend on this notebook. Good luck in your studies! PASS leader: Fatema Habib Special thanks for: - Mr. Husain Naser - Maryam Taraif - Sayed Ali Alawi  Professionalism and procedures - Effective communication: 1. Respectful communication: - Respect - Ask for permission - Actively listen to the problem - Stay professional - Avoid interruptions on customer time 2. Electing answers: - Use non-accusatory communication - Ask fact-seeking questions 3. Explaining what you’re doing: - Avoid jargon, acronyms, and abbreviations - Use analogies and visual aids when possible - Stay friendly - The Traits of a Tech: 1. Dependability Follow the ethics of reciprocity 2. Responsibility (Golden Rule) 3. Honesty 4. Integrity Professionalism * Follow the process to achieve an effective communication: Arrive early, or call well in advance if you need to reschedule Listen to the user (As mentioned under Respectful communication) Ask follow up questions (As mentioned under Eliciting Answers) Identify the problem Identify the probable cause Propose a solution (Here you may ask the user to sign Authorization to work document, or provide a quotation with cost and/or time) Start your work (As mentioned under Explaining what you are doing) ◦ If you could not fix the problem, escalate it Ask the user to test and verify that the problem is fixed ◦ Communicate your results with the user, their manager, and your manager ◦ At this point you can ask them to sign any type of forms you require like a delivery note Follow up the next day with the user to ensure their satisfaction with the work before you close the ticket Document everything including what you did Professionalism * Tools of the Trade and Personal Saftey Electrostatic Discharge (ESD): the person of static electrical charge into your PC components such as RAM stick. - it can destroy delicate electronic components. * Physical Safety - Consider personal safety issues such as: 1. Messy cables 2. Heavy items (lift with legs) 3. Hot components (Monitor, printer) 4. Computer Repairs (remove jewelry) 5. Carpentry work (ware air filter mask and safety goggles) Electromagnetic pulse (EMP): the transfer of electromagnetic energy from one source to another in such a way that causes damage. Electromagnetic interface (EMI) Radio frequency interface (RFI) ——> just a sound Professionalism * Software license types: 1. EULA (end-user licensing agreement) restricts how app can be used and transfer rights. 2. Open-source licenses: - Freely accessed, used, changed, shared by anyone. 3. Commercial licenses (closed source): - Source code not included. - Limits on how users can use object code (app). 4. Personal license: - License can be bought at retail stores. - For personal/individual use. - The license can cover one user (PC) or as a family package. - Example: Windows (home/student). 5. Enterprise license: - Includes apps that are not available in the personal license. - More management and security features. - License depends on business requirements to cover CPUs, device or users. - Different rales to upgrade. Professionalism * Digital Rights Management (DRM): - Software or service mechanisms that limit the end-user’s rights to copy, transfer, or use software or digital media. - Before upgrading a system, find out how upgrade will affect DRM issues. - Before removing a system with DRM apps from service, find out what happens to DRM licenses. Professionalism * Antistatic Tools 1. Antistatic wrist strap - Keeps you and the PC at the same electrical potential to prevent ESD. 2. Antistatic Mat - Used temporarily to place parts taken out of the PC. 3. Antistatic Bags - Shed static electricity when touched. - Used to store electrical components from your PC. Antistatic wrist strap in use Antistatic wrist strap and mat combination These antistatic Wrist strap > devices use tiny self grounding resistors. Professionalism * Physical Tools - Basic tech Toolkit contains: a Philips-head screwdriver, nut drivers, flat-head screwdriver, torx… etc. (No hammers) - Including magnifying glass, small flashlight, and plastic tweezers. - There are kits for mobile devices. Toolkit  The visible computer * Computer: an electronic device that can perform calculations. Typical PC Various types of computers - runs Microsoft - General: purpose computing Windows devices - used for various - Specific: purpose computers tasks - Devices with computing inside, ex: cars * The computing parts 1. Hardware: physical components you can touch (keyboard, Mouse) 2. Operating System (OS): controls hardware and enables user to tell the computer what to do (Windows, Mac, Linux) 3. User interface (UI): software with which you can interface 4. Graphical user interface (GUI): offers images or icons to select (Chrome, firebox) 5. Applications (programs): Allow you to do specialized tasks on a computer. The visible computer * Computing process: 1. Input: get data into the computer (Mouse, touch screen) 2. Processing: tell hardware what to do (CPU) 3. Output: show the result (Monitor, speaker) * Additional stages on modern computers - Data storage: saving a permanent copy of work - Network connection * Computing Hardware The visible computer The visible computer The visible computer * Definitions and terms - The system unit: the main part that contains CPU, brain of the system, RAM, hard drives (all the stuff we need to actually make the computer run) - Monitor: it allows us to see what the computer is doing and it is the primary of the output interface - Universal Serial Bus (USB): the most used - Rectangle connection (network cable connection): we use these using a type of connector called RJ45 -to get a wired network- - Round connecter : for the speakers and sound - Digital visual interface (DVI): an older type of video connection - Video graphics array (VGA): an older style video connector it was used to push monitors The visible computer * Inside the PC - Motherboard (the black rectangle): the primary device by which we connect all the innards of the system unit together (RAM,CPUs,internal hard drives) all connects together via motherboard The motherboard has power connections (that’s what actually gives power to everybody). - RAM stick: doesn’t say how many megabytes or gigabytes "its just a stick". - Liquid cooling system: fans, liquid runs in there it takes away the heat that CPU makes. - Thermal paste: provides a really good thermal seal it provides a good heat conductor between CPU and the cooling system. - Mass storage (M.2 SSD): the primary storage for the system. - Chipsets: it defines all the different features that the motherboard can do (how many USB ports / how many hard drives it can support etc..) - Power connector: things that allows us to on/off switch, reset button etc.. The visible computer The visible computer * What is a computer? In order to be a computer , you have to have a processor, RAM, mass storage and operating system. - CPU (the brain of the computer): the cornerstone of any computer. - Mass storage & Hard drives: they store data whether it is a program, doc, when you are not using it Hard drives are fast but they're not nearly as fast as a CPU. When you are running a program you are taking a copy of that program off of the mass storage and putting it into RAM - RAM: super fast not as fast as a CPU but it is very fast (RAM IS VERY EXPENSIVE) * Saving your data: The CPU will instruct the data that you've written on RAM -you hit files save- that’s copied also to mass storage Mass storage stores 2 different things: - Programs you are not using - Stores our data (pics, doc, games) The visible computer * What is Operating System (OS)? - The kernel (built into operating system): the core part of the operating system that handles the primary memory management (if somebody wants to start a program it's the kernel that decides where is that program going to sit in your RAM, how often will it run etc..) The kernal job is to act as a conductor to keep all things running. When we run a program it goes from the hard drive,then comes on onto RAM When program starts to run we call it a process - process ID (PID): every single program that is running in memory right now gets its own unique process id. They dedicate a certain number of wires just to be able to talk to the memory (Nowadays it is 64 bits) The idea of an operating system is that it knows exactly how to talk to a particular type of CPU - You have to know based on whatever cpu based on your computer which operating system for you to get (Most of 64- bit operating systems runs both 32 & 64 bit of programs). Operating systems use device drivers to talk to hardware.  Microprocessor (CPU) * The Central processing unit (CPU) works as a powerful calculator. * The CPU communicates with the outside world using the External Data Bus (EDB): - Uses binary (1 is on, and 0 is off) to communicate. - Data lines on the bus can be switched (on or off) from inside or outside. * Components of the CPU 1. Registers - Four general-purpose registers found in all CPU’s: AX CX BX DX 2. Code book (Instruction set) - Every CPU has its own code book. - Used to understand the commands (machine language) Ex. 00000100 —> The number 4 3. Clock - The CPU does not work until told to, the clock tells the CPU its time to work. A charge on the clock wire tells the CPU it is time to work. ——> Microprocessor (CPU) ——> * Clock Cycle: one complete up and down segment of the sine wave. - A clock cycle is the time it takes for the clock wire to charge. - Every command requires at least two clock cycles. * Clock speed: its the minimum number of clock cycles the CPU can handle in a given time period. - Clock speed is measured in hertz: * One cycle per second = 1 hertz (Hz) - Modern CPUs run at 3+ GHz. 4. System crystal (found on the motherboard) - System crystal governs CPU run speed. - Crystal can clock a CPU with a rated speed higher than the crystal, but the CPU will operate at the slower speed of the crystal. * A 1 GHz crystal can clock a 2 GHz CPU, but the CPU will operate only as fast as the crystal clock (1 GHz). - Underclocking: means running a CPU slower than its rated clock speed, it does not take advantage of all the power of the CPU. - Overclocking: means to run a CPU faster than its maximum clock speed, it can overheat the CPU. Microprocessor (CPU) 5. Memory - A program is stored on the hard drive. - Hard drivers can’t give the CPU data at a fast speed. - Devices that hold ones and zeroes that the CPU accesses are called Memory. * RAM - RAM is organized like a spreadsheet, each row holding eight bits (A bit is a one or zero). - RAM transfers and stores data to and from the CPU in byte- sized chunks. - Computers use dynamic RAM (DRAM) for main memory. 6. Address Bus -CPU and RAM use external data bus (EDB) to send and receive data and instruction commands. The CPU addresses the MCC using the Address bus to let it know which memory address it needs, The MCC knows where the data is located in the RAM so it will bring it from its address location, and will then put the data on the External Data Bus to send it back to the CPU. - CPU needs a helper chip to get data from the RAM, this chip is called Memory controller chip (MCC). - The address bus is separate set of wires from the EDB, it enables the CPU to control the MCC. It tells the MCC what it wants from the RAM. - The number of wires in the address bus determines the maximum amount of RAM the CPU can handle. Microprocessor (CPU) * Bits and Bytes - Any individual 1 or 0 = a bit - 4 bits = a nibble - 8 bits = a byte - 16 bits = a word - 32 bits = a double word - 64 bits = a paragraph or quad word Bits are represented by “b” Bytes are represented by “B” * First byte of RAM represented by twenty zeroes. * Last byte of RAM represented by twenty ones. * Saving energy by making the CPU run more slowly when there’s no demand is called throttling. Microprocessor (CPU) * Ways of CPUs have been improved: 1. Clock multipliers 2. 64-bit processing 3. Virtualizing support 4. Parallel execution 5. Multicore processing 6. Integrated memory controller (IMC) 7. Integrated graphics processing unit (GPU) 8. Security * Clock multipliers - All modern CPUs run at some multiple of the system clock speed. * 64-bit processing - EDB and address bus size increased. - Most new CPUs support 64-bit processing. * Virtualization support - Modern CPUs have built-in support for running more than one operating system at a time. Ex. Running Linux on Windows * Parallel Execution - Modern CPUs process multiple commands and parts of commands in parallel execution. Microprocessor (CPU) * Pipelining - CPU talks at least four steps (stages): 1. Fetch: Get the data from the EDB. 2. Decode: figures out what type of commands needs to be executed. 3. Execute: perform the calculation. 4. Write: send the data back onto the EDB. * Cache - A cache reduces wait states by using built-in, very high- speed RAM called static RAM (SRAM). - The cache on the CPU called the L1. - The cache on the motherboard is called the L2. - Newer CPUs include three caches. - The address bus and the EDB (connecting the CPU, MCC, and RAM) are called the frontside bus. - The connection between the CPU and the L2 cache is called the backside bus. * Multithreading - Means running multiple threads at the same time (hyper- threading). * Multicore Processing - Multiple CPUs combined into a single chip, executing multiple threads at ones (Dual-core architecture). Microprocessor (CPU) * Integrated Memory Controller (IMC) - Moved from the motherboard chip into the CPU to optimize flow of information into and out from the CPU. * Integrated Graphics Processing Unit (GPU) - Handles the video processing portion of computer tasks. - Ideal for mobile devices. * Security - NX bit technology in all modern processing: 1. Enables CPU to protect certain sectors of memory. 2. Steps malicious attacks from getting to essential OS files. * Installing issues - Pay attention to: 1. CPU pins. 2. Power supply. 3. Adequate cooling. * Socket types 1. Intel: Land Grid Array (LGA). 2. AMD: Pin Grid Array (PGA). Microprocessor (CPU) * Additional information from videos: - CPU socket: the mount where a CPU connects to the motherboard. - Almost every 64-bit of CPU can run 32-bit CPU. - Thermal paste or heat dope: it is used as a barrier or like a way to pull the heat even better from the CPU into the cooling system itself. - Always use thermal paste between the CPU and the fan. - Liquid cooling uses a pump, a radiator and a cooling block with liquid to remove heat. Microprocessor (CPU)  RAM (Memory) * What is the use of RAM? - It is the component between the hard drives and the CPU, it gives the CPU what it wants from the hard drives. - RAM is a volatile memory. When you run a program, it gets copied from the Hard disks to the RAM and will stay in RAM while it is running. All data in RAM gets cleared when the machine is powered off (unlike your Hard disks HDD/SSD which keep their content even when the machine is off). * Different motherboards support different types of RAM. * Type of RAM: 1. Synchronous DRAM (SDRAM) 2. Rambus DRAM (RDRAM) - no longer available 3. Double Data rate SDRAM (DDR SDRAM) 4. DDR2 and DDR3 5. DRR3L and DDR3U 6. DDR4 * Synchronous DRAM (SDRAM) - (168 pins) - Synchronized with the system clock. - Came on stick called dual inline memory module (DIMM). - Laptops used small-outline DIMM (SO-DIMM). * Double Data Rate SDRAM (DDR SDRAM) - (184 pins) - Faster RAM supported by AMD and other manufacturers. - Commonly referred as DDR. - Doubles the throughput over SDRAM (two processes in one cycle). - Dual-channel architecture: uses two sticks of RAM together. ——> RAM (memory) ——> - To determine the speed of the DDR: Clock speed x2 DDR speed rating x8 PC speed rating 100 MHz DDR - 200 PC - 1600 133 MHz DDR - 266 PC - 2100 * DDR 2 (240 pins) - An improved version of DDR which runs faster on less power. - To determine the speed of the DDR 2: Clock speed x4 DDR2 speed rating x8 PC speed rating 100 MHz DDR2 - 400 PC2 - 3200 166 MHz DDR2 - 667 PC2 - 5300 - Note: Each RAM generation has a notch cut in the pins at different locations to stop any confusion. That means you cannot accidentally mix your RAM modules up or damage your motherboard, even if you buy the wrong type. RAM (memory) * DDR 3 (240 pins) - It has higher speed, more efficient architecture and 30% lower power consumption than DDR2. - It doubles the buffer of DDR2 from 4 bits to 8 bits. - Some chipsets that support DDR3 also support triple- channel (supported by intel’s LGA + not supported by AMD) and quad-channel architecture (supported by recent intel and AMD). - To determine the speed of the DDR 3: Clock speed x8 DDR3 speed rating x8 PC speed rating 100 MHz DDR3 - 800 PC3 - 6400 200 MHz DDR3 - 1600 PC3 - 12800 * DDR3L / DDR3U - DDR3L is a low voltage version of DDR3 ( runs at 1.35 volts). - DDR3U is ultra-low voltage (runs at 1.25 volts) RAM (memory) * DDR 4 (288 pins) - It offers higher density and lower voltages than DDR3, and can handle faster data transfer rates (runs at 1.2 volts). - To determine the speed of the DDR: Core Clock speed x8 DDR4 speed rating x8 PC speed rating 200 MHz DDR4 - 1600 PC4 - 12800 300 MHz DDR4 - 2400 PC4 - 19200 * RAM variations - There are two types of RAM: 1. Single-side RAM 2. Double-side RAM - Some motherboards can’t use double-side sticks. * Latency: the delay the RAM takes to respond - Numbers reflect how many ticks of the system clock it takes before the RAM responds. - RAM with lower latency “Ex. CL6” is faster than RAM with a higher latency “Ex. CL9”. RAM (memory) * Parity and ECC - The parity RAM allows the computer to detect wether an error occurred in the reading or writing of data in memory. - Error correction code (ECC) RAM is an improvement over parity, detecting as well as correcting errors (used only on high-end systems). * Registered and Buffered memory - Registered (buffered) RAM refers to a small registers installed on some memory modules to act as a buffer (cache) between the DIMM and the memory controller. - The motherboard will either use a buffered RAM or unbuffered RAM, it can’t use both. * Working with RAM - Adding more RAM almost always improves overall system performance to obtain desired results: 1. Determine whether the RAM is the cause of system problems. 2. Pick the proper RAM. 3. Use good installation practices. * How do you know you need more RAM? - General system sluggishness. - Excessive hard drive accessing (programs take forever to load). RAM (memory) Serial Presence Detect (SPD) technology detects and automatically sets up installed * Virtual Memory DIMM. - It’s a portion of the hard drive used as an extension of RAM. It is set aside as a page/swap file. - It is used when the PC runs of real RAM, the system swaps programs from the RAM to the page file. - Disk thrashing occurs when the operating system needs to access the page file too frequently. - Ready Boost feature enables use of USB flash drives as virtual memory (faster than HDD). * System RAM Recommendation 1. 32-bit windows: 2GB to 4GB 2. 64-bit Windows: 4GB to 16+ GB 3. OS X: 4GB to 8+ GB 4. Linux: can run it smoothly on 2GB only. - You can use the system control panel (property sheet) to know your current RAM capacity. * Getting the right RAM - Different RAM sizes aren’t always handled well in motherboards. It is better not to mix speeds. - It is recommended to choose RAM sticks that match technology, capacity, speed. Otherwise the system may be constantly crashing or result in corrupted data. RAM (memory) *Memory errors can include: - Page Fault: not necessarily RAM problems. - Non-maskable interrupt (NMI): panic button inside the PC. - Manifests as proprietary crash scree: Blue Screen of Death (BSoD) in Windows Vista and Windows 7 and the pinwheel of death in Mac OS X. - Not all intermittent errors are RAM-related. - Dying power supply, electrical interference, and buggy applications or hardware can also produce intermittent errors. - If your newly installed RAM is not recognized by your system and it still show the older RAM capacity you had, then it could be improperly installed or was installed without following the dual channel architecture guidelines of the motherboard so a reinstallation might be required. However, if your system does not even boot or power on after installing a new RAM, then your RAM stick or the SPD chip might be physically damaged.  Motherboards - The motherboard provides the foundation for the personal computer. It contains wires called traces. * How does it work? 1. The form factor, determines: - The size of the motherboard. - General location of components and parts. 2. The chipset, determines: - Type of processors and RAM supported. 3. Built-in components, determines: - The core functions of the system. * Form factors The form factors defines: 1. Size, shape and layout of the motherboard and also the type of case you need. 2. Power supply interface type. 3. The air flow around the case. - For upgrades, you need to know the form factors. Motherboards * Type of form factors: 1. ATX (The most used in the current time) - CPU and RAM are placed close to each other to provide easier access. - RAM is closer to northbridge and CPU for better performance. 2. MicroATX (used in smaller machines and builds) - A smaller version of ATX with less slots. - Fits in standard ATX case or microATX case. 3. Mini-ITX (used in sale machines) - It’s the largest and most popular of three ITC form factors. - Some companies has its unique form factor which they created. * Chipset The Chipset determines: 1. The processor type. 2. Type and capacity of RAM. 3. The internal and external devices supported by the motherboard. Motherboards - Early chipset offered Northbridge and Southbridge. - Modern chipset features Southbridge only (CPU handles Northbridge functions). * The Northbridge: 1. Helps the CPU to work with RAM. 2. Communicates with video on newer AMD systems. * The Southbridge: - Handles expansion devices and mass storage drives. * Both of the Northbridge and Southbridge together are called Chipset * Super I/O chip: - Provides support for legacy devices. * Motherboard Built-in components 1. Case fan support - Every motherboards has a CPU fan power connector, usually a four-wire connector that also supports three-wire fans. - Can be monitored and controlled in Windows. ——> Motherboards ——> 2. Expansion Bus - To expand the functionality of the motherboard. - The slots and accompanying wires are called expansion bus. - The slow devices slots are connected to the Southbridge. - The fast devices slots are connected raptor the Northbridge. - The system crystal will govern the CPU speed, not the expansions you are putting. - The expansion crystal will govern the speed of the expansions you put. 1) PCI(original was 32 bits ran at 33 MHz) - It provided a wider, faster more flexible alternative than any expansion bus. - PCI devices are play-end-play, which means the motherboard will recognize it when plugged. 2) AGP - A specialized, video-only version of PCI. - Used only for video cards (GPU). Motherboard 3) PC-x - A high-speed alternative PCI. - Often used in business workstation. - Got discontinued when PCI Express came out. 4) PCI Express (PCIe) - The latest, fastest, and most popular expansion bus used today. - PCI Express is still PCI, but it has its own direct connection (a point-to-point connection)to the Northbridge, it doesn’t not share its bus. - Sends the data serially, not in parallel way. - Transfer rate describes number of operations happening per second. - Most common PCI Express slot is the 16-lane (x16), used for video cards. * Installing expansion bus requires: 1. knowledge - Check if your motherboard and system supports the expansion device. 2. Physical installation - Don’t touch the chips. - secure all cards properly. - Use anti-static gloves and mat. Motherboard 3. Device drivers - Install the device driver after inserting the Devi from the manufacturer’s website or CD. 4. Verify - Use Device Manager to verify that Windows sees the device. - Test the functionality of the device. * Troubleshooting Expansion Cards - Device Manager provides the first diagnostic and troubleshooting tool in Windows. - If the Device Manager does not recognize the new device, one of two problems exists: 1. Device is physically damaged, 2. There is a problem with the device drivers. * Device Manager error codes: - Indicates that a device is missing, or the device isn’t recognized, or a device driver problem. - Indicates a disabled device (turned off manually or damaged). - A device producing this error will not work. Motherboard * To correct the error: 1. Double-check the device’s connection. 2. Try reinstalling the driver with the update drivers buttons. 3. Check that the device isn’t disabled. * Installing a Motherboard 1. Remove all the cards. 2. Remove obstructing drives. 3. Remove the power supply (only if necessary). 4. Unscrew the old motherboard (Motherboard mounts to the case with small connectors called standoffs). * Troubleshooting Motherboards - Failures fall into three types: 1. Catastrophic 2. Component 3. Ethereal * Catastrophic failure: 1. System will not boot. 2. Due to defects (rarely occasion). 3. ESD shock. 4. To fix, replace the motherboard. Motherboard * Component failure (happens rarely) 1. Faulty component. 2. Buggy device driver. 3. Buggy application software. 4. Corrupted OS. 5. Over heating and power supply problems. * Ethernet symptoms: 1. Things don’t work all time. 2. PC reboots itself. 3. Blue screens of death. - cause includes components failure. * To deal with the failure - Catastrophic failure: replace the motherboard. - Components failure: consider to replace the device.  Storage Technologies * HDD (Hard disk drive) - HDD is composed of individual disks or platters made from aluminum and coated with a magnetic medium. - Two tiny read/write heads service each platter. - HDDs run at a set spindle speed measured in revolution per minute (RPM). - 5400, 7200, 10000 and 15000 are common speeds. - More speed = better performance but means over heating. * SSD (solid state drive) - Based on semi-conductors and transistors, no moving parts. - Form factors: 1.8 inch, 2.5 inch, 3.5 inch (rare). - Variations: mSATA, M.2, add-on PCIe cards. - Operates by writing data to high-speed flash memory cells. - Windows supports hybrid hard drives, meaning you can have both HDD and SSD in a PC. It’s better to have both SSD. Storage technology cluster is also sometimes called allocation unit Storage technologies * Parallel and serial ATA - Advanced Technology Attachment (ATA). - Parallel ATA (PATA): sends data in parallel. - Serial ATA (SATA): sends data in serial on one wire. 1. SATA - point-to-point connections between SATA device and the host bus adapter (HBA). - 30 times faster than PATA. - Maximum cable length 1 meter (internal). * SATAe or SATA 3.2 - Ties capable drives directly into the PCI Express bus on motherboard. - Enhances speed of throughput. - Requires motherboard which supports SATAe. 2. External SATA (eSATA) - Extends the SATA bus to external devices. - Up to 2m cable length. 3. AHCI - Advanced Host Controller Interface (AHCI) is an option in Blos menu which you should enable if you will be using HDD (before installing the operating system). - Enable NVME if you will be using SSD. Storage technology Motherboard * Protecting Data with RAID - There are serval ways to protect data: 1) Disk Mirroring: read and write data at the same time to two drives. 2) Disk Duplexing: a separate controller for each drive. 3) Disk Striping: Spreading the data among multiple drives. 4) Disk Striping with Parity: adds parity data that can be used to rebuild. * RAID (Redundant Array of Independent Disk) 1. RAID 0 (Disk Striping) - Requires at least two drives. - No redundancy. 2. RAID 1 (Disk Mirroring / Duplexing) - At least 2 hard drives. - Requires double storage space. 3. RAID 5 (Disk Striping with distributed Parity) - Distributes data across all drives. - Fastest way to provide redundancy. Motherboard 4. RAID 6 (Disk Stripping with extra Parity) - RAID 5 with extra Parity data. - Larger array of disks. 5. RAID 10 (Nested, striped mirrors) - 1 pair of mirrored disks, and another pair mirrors the first pair. 6. RAID 0+1 (Nested, mirrored stripes) - Starts with two RAID 0 striped arrays, then mirror the two arrays to each to each other. Motherboard Motherboard Motherboard Motherboard  Display Technology * In order to display a video, you need: 1. Monitor 2. Cable 3. Video card * Type of lightning: * Video Displays Technologies 1. CCFL (flickering 1. CRT (cathode Ray Tube) after a period of time). 2. LCD (Liquid Crystal Displays) 2. LED (Better). 3. LED (Light Emitting Diode) 4. OLED (Organic LED) 5. Projectors - Refresh rate: the time it takes for the monitor to redraw a whole screen. - Individual pieces of the picture are called pixels. Each pixel has sub-pixels. - Resolution: the number of horizontal pixels times number of vertical pixels. * CRT Monitors - Uses phosphor coating, electron stream, electron guns and yoke. - Has vertical and horizontal refresh rate. - Contrast ratio is non-adjustable (fixed). Display Technology * LCD Monitors - Early LCD screens used a matrix of wires for charge. A charge is required to light each single sub-pixel. - Passive matrix charges one line at a time. - Dual-scan passive matrix charges two lines at a time. - More recent LCD monitors uses active matrix technology: - Uses TN technology (older, cheapest and faster). - Uses IPS technology (most used). - Inverters in the LCD monitors converts PC power to AC power to run the backlights. - Transformers converters AC power to DC to run the logic board. - The brightness is determined by the backlights, measured in nits. - Response Rate is the time it takes all the sub-pixels to go from pure block to pure white and block again. * Projectors - Two type: 1. Rear view projector. 2. Front-view projectors (most common). - Uses Digital Light Processing (DLC) - Lumens is the brightness in the projectors. Display Technology * Plasma Display - Plasma Displays Panels (PDP) is often used for Tux, not computers. - Consumes more electricity. * Cables (connectors) - VGA - DVI - HDMI - Display port (Dport) * Display Adapter (Graphics cards) - Aspects that define a video card: 1. Display modes 2. Motherboard slot 3. Graphic processor circuity 4. Video memory (VRAM) 5. Integrated GPUs 6. Connection - Some motherboard have a built-in GPU. * Modes - Color depth is represented as bits. Display Technology * 3D Graphics - Used to create images with the same depth and texture as objects seen in real world. - Early 3D games used sprites. - The 2nd generation produced 3D Graphics objects through a process called rendering. - Objects are composed of a group of points (vertices). - Vertices are connected with lines. Forming polygons. - The last step is adding image files called texture. - 3D Graphics rendering requires large amount of GPU. - APIs (Application Programming Interfaces) came up to enhance the rendering process. * Troubleshooting videos - Problems in the video card: 1. Overheating. 2. Corrupted drivers. - Monitor Problems: 1. Ghosting. 2. Missing Color. 3. Loss of brightness. - Use Anti-static monitor to clean, avoid commercial products. Display Technology * Resolution and aspect ratio First gen used 4 by 3 aspect ratio : 16 by 10 ratio: golden ratio Display Technology 720 P: 1080 P: 4 K: 5 K: Questions Questions - professionalism Answers - professionalism Questions - Microprocessors Answers - Microprocessors Questions - Motherboard Answers - Motherboard Questions - RAM Answers - RAM Questions - Storage technology Answers - Storage technology Questions - Display technology Answers - Display technology Wish you all the best! Fatema Habib