Computer Maintenance SN43001FP — Study Notes (Chapter I: Install System Hardware)

1.1 Features and functions of computer components

  • A computer system consists of hardware and software components.
    • Hardware: physical equipment such as case, storage drives, keyboards, monitors, cables, speakers, printers.
    • Software: operating system (OS) and programs.
    • The OS instructs the computer how to operate; programs or applications perform different functions.
    • Personal computer: small computer for a single user; desktops and laptops are two types of PCs.
  • Objectives outline the scope of Chapter 1.1: features of components, workplace safety, safety procedures for installation, installation procedures, and BIOS/UEFI settings.
  • Topics covered under 1.1.1 to 1.1.9 include cases/power supplies, motherboard, CPU, memory, adapter cards/expansion slots, storage (HDD/SSD), optical storage, storage interfaces, and cables.

1.1.1 Cases and Power Supplies

  • Computer chassis (case) houses core components: power supply, motherboard, CPU, memory, disk drives, and adapter cards.
  • Form factor refers to the physical design/size of a case.
  • Common desktop form factors:
    • Tower (Mini, Mid-size, Full-size)
    • Small Form Factor (SFF)
    • Slim Line
    • Desktop case
    • All-in-one
  • Power supply unit (PSU) converts AC power to the lower DC voltages used by internal components.
  • Desktop PSU form factors include:
    • AT (Advanced Technology) – original, obsolete
    • ATX – updated version of AT, widely used but being superseded in some designs
    • ATX12V – most common today; includes a second motherboard connector for CPU power
    • EPS12V – originally for servers, now common in high-end desktops
  • Common PSU connectors:
    • P1 (20-pin or 24-pin) – motherboard power
    • P4/ATX12V (4-pin or 8-pin) – CPU power
    • Molex (4-pin) – IDE drives and optical drives
    • Berg (Mini-Molex) (4-pin) – floppy drives; sometimes used for other auxiliary connections
    • Serial ATA power (SATA) – for SATA drives (15-pin power? note: SATA power is a 15-pin connector)
    • PCIe power connectors (6-pin or 8-pin) – for PCIe graphics cards
  • Voltage and protection:
    • PSU voltages: commonly 3.3 V, 5 V, and 12 V; some rails are single, dual, or multi-rail.
    • The power supply may include a dual-voltage selector switch (110/115V and 220/230V) on some units; dual-voltage PSUs adjust input voltage; some PSUs auto-detect.
    • Capacitors inside PSUs can hold charge; do not open a power supply.
  • Wattage and electrical basics:
    • Four basic electrical units to know: Voltage $V$, Current $I$, Resistance $R$, Power $P$.
    • Ohm’s Law: V=IRV=IR
    • Power relation: P=VIP=VI
  • Efficiency and standards:
    • 80 Plus certification: voluntary program to promote efficiency; products certified if they are >80% efficient at 20%, 50%, and 100% of rated load.

1.1.2 Motherboard

  • The motherboard (system board) is the main printed circuit board that houses buses and data pathways.

  • It accommodates:

    • CPU, RAM, expansion slots, heat sink/fan, chipset, sockets, BIOS/UEFI, I/O ports, and interconnect wiring.
    • All devices communicate with the CPU on the motherboard; peripherals connect via cables.

  • I/O ports examples: keyboard, mouse, USB, audio ports, etc.

  • Power/connectors on board:

    • 24-pin ATX main power connector
    • 8-pin (or 4+4) CPU power connector

  • Form factors (board size/layout) influence power supply compatibility and case size:

    • ATX (standard)
    • Micro-ATX
    • ITX (Mini-ITX)

  • Chipset concept:

    • Northbridge: controls high-speed access to RAM and video; connects to CPU/memory/graphics
    • Southbridge (or PCH in modern designs): handles slower devices (HDD/USB/PCIe slots, etc.)
    • Some CPUs include memory controllers on the CPU itself (e.g., newer Intel architectures)

  • Memory architecture on the motherboard:

    • Memory slots (RAM) connect to CPU via the chipset; memory types and speeds must be compatible with the CPU and chipset.

  • Example layout highlights (from a typical motherboard illustration):

    • 24-pin ATX power connector, 8-pin CPU power connector
    • CPU socket (varies by socket type)
    • RAM slots (dual-channel capable)
    • Expansion slots: PCIe, PCI, etc.
    • I/O ports on rear panel (e.g., USB, Ethernet, audio)

  • Important concept: motherboard form factors determine which components and which power supplies are compatible.

1.1.3 Central Processing Unit (CPU)

  • Role and function:
    • The CPU interprets and executes commands from hardware and software, acting as the computer’s brain.
    • The CPU package is a microchip; CPU sockets on the motherboard host the processor.
    • Major manufacturers: Intel and AMD.
  • CPU sockets and packaging:
    • PGA (Pin Grid Array): pins on the underside of the CPU; inserted into a ZIF socket on the motherboard.
    • LGA (Land Grid Array): pins on the socket; CPU has flat pads; designed to be less fragile.
  • CPU architectures:
    • RISC (Reduced Instruction Set Computer) – smaller instruction set, faster per instruction
    • CISC (Complex Instruction Set Computer) – larger instruction set, fewer steps per operation
  • CPU enhancements and features:
    • Hyper-Threading (Intel): enables multiple threads to run simultaneously in a single CPU, effectively appearing as multiple CPUs
    • HyperTransport (AMD): high-speed interconnect between CPU and Northbridge
  • Performance measures:
    • Clock speed: MHz or GHz (cycles per second)
    • Front Side Bus (FSB) width: data bus width between CPU and chipset; wider FSB increases data transfer capacity (32-bit or 64-bit)
    • Multicore: multiple cores on one CPU die; more cores can execute more instructions concurrently; RAM is shared across cores on the same chip
  • Overclocking and throttling:
    • Overclocking: running CPU above its rated speed to boost performance; not recommended due to risk of damage
    • CPU throttling: reducing speed to conserve power or reduce heat
  • Integrated vs dedicated graphics:
    • Some CPUs include an integrated GPU; integrated GPUs share system RAM; suitable for non-intensive graphics
    • Dedicated GPUs have their own video memory (VRAM) and typically offer better performance for demanding graphics tasks
  • CPU technologies and memory:
    • Cache memory (L1, L2, L3): closer to CPU cores; faster, smaller caches (L1 fastest, L3 largest)
    • Cache stores copies of frequently used data from main memory to speed up processing
  • Cooling and thermal design:
    • Case fans to move air through the case
    • CPU heatsink with or without fan (passive vs active cooling)
    • Thermal design power (TDP): maximum heat (in watts) a chip is designed to generate; higher TDP generally means more cooling is needed
  • CPU-related terms:
    • TDP (Thermal Design Power): indicates heat/Power usage and helps determine cooling and PSU needs
    • Hyper-Threading (Intel) and HyperTransport (AMD) are CPU feature enhancements
    • Virtualization: hardware feature allowing a single processor to run multiple OSes in separate virtual machines
  • CPU cooling systems (brief): case fan, CPU heatsink, CPU fan; advanced graphics card cooling; water cooling sometimes used for high performance systems

1.1.4 Types of Memory

  • Memory fundamentals:
    • Memory chips store data as bytes (8 bits per byte)
    • ROM (Read-Only Memory) is non-volatile; contains instructions used at boot and startup; located on motherboard and other boards
  • ROM types and descriptions:
    • ROM: information written during manufacturing; cannot be erased or rewritten (obsolete)
    • PROM (Programmable ROM): blank at manufacturing; programmable once
    • EPROM (Erasable PROM): non-volatile but erasable with UV light (windows on chip)
    • EEPROM (Electrically Erasable PROM): can be programmed/erased in-circuit; often used for BIOS; flash ROMs
  • RAM (Random Access Memory): volatile, temporary working storage; more RAM improves performance; motherboard/memory limits apply
  • RAM types (overview):
    • DRAM (Dynamic RAM): older main memory; requires constant refreshing
    • SDRAM (Synchronous DRAM): synchronized with memory bus; supports overlapping read/write
    • DDR SDRAM families: DDR, DDR2, DDR3, DDR4 – transfers data faster than previous generations; different pin counts and voltages; lower voltages improve power efficiency
    • GDDR SDRAM: Graphics-focused RAM for GPUs
    • SRAM (Static RAM): fast, used for caches; higher cost; needs constant power
  • Memory modules and pins:
    • DIP (Dual Inline Package): single chip memory with pins on both sides
    • SIMM (Single Inline Memory Module): older module; 30-pin or 72-pin varieties
    • DIMM (Dual Inline Memory Module): holds SDRAM/DDR/DDR2/DDR3/DDR4 chips; pin counts vary by type:
    • SDRAM DIMM: 168-pin
    • DDR SDRAM DIMM: 184-pin
    • DDR2 DIMM: 240-pin
    • DDR3 DIMM: 240-pin
    • DDR4 DIMM: 288-pin
    • SODIMM (Small Outline DIMM): laptop/compact form; pin counts vary by generation (e.g., 144, 200, 204, 260 pins)
  • Memory speeds and designations:
    • DDR3-800, DDR3-1066, DDR3-1333, DDR3-1600, etc. Designations combine clock rate, I/O bus clock, and data rate (e.g., PC-6400, PC-8500, PC-10600, PC-12800, PC-14900, PC-17000)
    • DDR3/DDR4 data rates correspond to higher MHz with lower voltages; higher speeds increase throughput but require compatible CPUs/motherboards
  • Dual channel/multi-channel memory:
    • Requires matching banks and often color-coded banks on motherboard; two or more modules can operate in parallel to double data paths
  • Error-checking memory:
    • Nonparity: no error checking
    • Parity: uses 1 extra bit for error checking
    • ECC (Error Correcting Code): detects and corrects single-bit errors and detects multiple-bit errors
  • Memory modules concepts:
    • Memory DIMMs sit in Memory/DIMM slots on the motherboard
    • Dual/Multiple channel configurations require matched banks for best performance
  • RAM speed vs CPU bus (FSB) compatibility and performance implications

1.1.5 Adapter Cards and Expansion Slots

  • Adapter cards add functionality or provide additional ports for devices (e.g., PCIe, USB, video, audio, NICs).
    • Examples of adapter cards:
    • Sound adapter (audio)
    • NIC (Network Interface Card) – wired networking
    • Wireless NIC – wireless networking
    • Video adapter – graphics capability
    • Capture card – captures video for storage/processing
    • TV tuner card – watch/record TV signals
    • USB controller card – additional USB ports
    • eSATA card – adds SATA ports via PCIe
  • Expansion slots:
    • PCI (older 32/64-bit, mostly obsolete now)
    • Mini-PCI (laptop form factor; Type I/II/III variants)
    • PCI-X (PCI eXtended; higher bandwidth, mostly obsolete)
    • Riser card (adds more expansion slots, often used in smaller form factors)
    • AGP (Accelerated Graphics Port; legacy slot, largely superseded by PCIe)
    • PCIe (PCI Express): serial bus with higher throughput; multiple lanes
    • PCIe slot types by lanes: x1, x4, x8, x16; more lanes mean higher bandwidth
  • PCIe performance and lanes (overview):
    • PCIe has versions 1.0, 2.0, 3.0, 4.0, 5.0 with increasing transfer rates per lane
    • Lane configurations determine total throughput; example per-slot throughput grows with version and number of lanes
  • PCIe transfer rate table (summarized):
    • Version 1.0: X1 2.5 GT/s (~250 MB/s); X4 1.0 GB/s; X8 2.0 GB/s; X16 4.0 GB/s
    • Version 2.0: X1 5 GT/s (~500 MB/s); X4 2.0 GB/s; X8 4.0 GB/s; X16 8.0 GB/s
    • Version 3.0: X1 8 GT/s (~984.6 MB/s); X4 3.94 GB/s; X8 7.88 GB/s; X16 15.8 GB/s
    • Version 4.0: X1 16 GT/s (~1969 MB/s); X4 7.88 GB/s; X8 15.75 GB/s; X16 31.5 GB/s
    • Version 5.0: X1 32 GT/s (~3939 MB/s); X4 15.75 GB/s; X8 31.51 GB/s; X16 63.0 GB/s
  • Notes:
    • Different sized PCIe slots support different maximum PCIe lanes
    • PCIe is now the dominant expansion interface due to higher speed and scalability

1.1.6 Types of Storage Devices

  • Storage devices provide non-volatile data storage (retains data without power).
  • Classifications by media type:
    • Magnetic storage (HDD, tape)
    • Solid-state storage (SSD)
    • Optical storage (CD/DVD/BD)
  • Magnetic storage – Hard Disk Drive (HDD):
    • Traditional magnetic disks; capacities from GB to TB
    • Spindle speeds commonly include 5400, 7200, 10,000, 15,000 RPM
    • Form factors include 3.5", 2.5", and 1.8" drives
  • Magnetic storage – Tape drives: archiving data; capacities from GBs to TBs; data retrieval may be slower due to tape rewind
  • Solid-state drives (SSD):
    • Storage in semiconductor flash memory; no moving parts; faster, quieter, more energy-efficient, more reliable than HDDs
    • Typical capacities from ~120 GB to several TB
    • Form factors:
    • Disc drive form factor (2.5", 3.5", 1.8") for boxed SSDs
    • Expansion cards (PCIe add-in cards)
    • M.2 form factor (compact module plugged into motherboard)
    • NVMe (Non-Volatile Memory Express): standard interface for SSDs over PCIe; enables high performance; no special drivers required
    • SSHD (Solid State Hybrid Drive): HDD with onboard flash cache to improve performance; cheaper than pure SSD but faster than HDD alone
  • M.2 SSDs and related concepts:
    • M.2 module: compact, 22 mm wide; lengths vary (30, 42, 60, 80, 110 mm)
    • Keys: B, M, B+M determine interface and lane support
    • M.2 slots can support SATA and/or PCIe (NVMe) interfaces depending on slot and module
    • M.2 interface key types and compatibility determinations:
    • B key: often SATA/PCIe x2 support
    • M key: PCIe x4 / NVMe support
    • B+M key: compatible with both; typically PCIe x2
  • Internal storage interfaces and standards (high level):
    • SATA: Serial ATA; main data interface for HDDs/SSDs; SATA power and SATA data cables
    • IDE (PATA/EIDE): legacy 40-pin (HDD/ODD) data interface; older standard
    • SCSI/SAS: alternate storage interfaces; SAS is Serial Attached SCSI used in servers
    • SATA revisions: SATA I/II/III with increasing data transfer speeds

1.1.7 Optical Storage Devices

  • Optical drives use lasers to read/write data on optical media (CD, DVD, Blu-ray).
  • Media types:
    • CD: data and audio storage
    • DVD: digital video and data storage
    • Blu-ray (BD): HD digital video and data storage
  • Media states: pre-recorded (ROM), recordable (WRITE-ONCE), and rewritable (READ/WRITE multiple times)
  • Disc layers:
    • DVD and BD media can be single-layer (SL) or dual-layer (DL); DL increases capacity roughly by a factor of two

1.1.8 Internal Storage Drive Interfaces

  • Storage devices connect to the motherboard using:
    • SATA (main modern interface for HDDs/SSDs)
    • Legacy Parallel ATA (PATA/EIDE) – older standard
  • Main SATA interface versions: SATA 1, SATA 2, SATA 3 (same cables/connectors with different speeds)
  • Other storage interfaces:
    • SCSI (older standard) and SAS (Serial Attached SCSI) for servers
  • M.2 interface specifics:
    • M.2 slots can support SATA or PCIe interfaces depending on the slot and key type
    • M.2 modules are keyed (B, M, B+M) to prevent incorrect insertion; slots may support multiple interface types

1.1.9 Internal converter, power and data cables

  • IDE (PATA) ribbon cables:
    • 34-pin ribbon cable used for floppy drives
    • 40-pin ribbon cable used for HDDs and optical drives
    • IDE uses Molex power connectors
  • SATA data and power cables:
    • SATA data cable: 7-pin data connector; L-shaped to ensure correct orientation
    • SATA power cable: separate power connector for SATA devices
  • Conversion/adapters:
    • Molex-to-SATA adapter cables used to connect SATA drives to Molex power cables

1.2 Workplace Safety & Health Act (Outline)

  • The transcript mentions this as an objective (1.2) but does not provide detailed content within the material provided.
  • Practical implication: in real-world settings, follow applicable safety and health regulations during installation and maintenance of computer systems.

1.4 Procedures for installing computer components (Outline)

  • The transcript lists this as an objective (1.4) but does not provide step-by-step installation procedures in the material provided.
  • Practical implication: refer to official installation procedures and safety guidelines when handling hardware components.

1.5 BIOS/UEFI Settings (Outline)

  • The transcript lists this as an objective (1.5) but does not provide detailed content on BIOS/UEFI settings in the material provided.
  • Practical implication: BIOS/UEFI settings govern core hardware initialization, boot order, security, and system performance tuning; familiarity is essential for maintenance and troubleshooting.

Important formulas and numerical references (LaTeX)

  • Ohm’s Law: V=IRV=IR
  • Power relation in circuits: P=VIP=VI
  • Typical PSU voltages used by digital logic and motors: $3.3$ V, $5$ V, and $12$ V
  • Power supply input voltages (dual-voltage switches): 110/115 V or 220/230 V
  • Common HDD spindle speeds (RPM): 5400, 7200, 10000, 15000
  • PCIe data rates (summary by version and lanes):
    • Version 1.0: X1 2.5 GT/s, X4 1.0 GB/s, X8 2.0 GB/s, X16 4.0 GB/s
    • Version 2.0: X1 5 GT/s, X4 2.0 GB/s, X8 4.0 GB/s, X16 8.0 GB/s
    • Version 3.0: X1 8 GT/s, X4 3.94 GB/s, X8 7.88 GB/s, X16 15.8 GB/s
    • Version 4.0: X1 16 GT/s, X4 7.88 GB/s, X8 15.75 GB/s, X16 31.5 GB/s
    • Version 5.0: X1 32 GT/s, X4 15.75 GB/s, X8 31.51 GB/s, X16 63.0 GB/s

Quick connections to real-world relevance

  • Understanding form factors helps ensure compatibility between chassis, motherboard, and PSU.
  • Recognizing connector types (P1, P4, Molex, Berg, SATA, PCIe) prevents incorrect wiring and hardware failure.
  • Distinguishing ROM vs RAM vs cache vs VRAM clarifies how data is stored, accessed, and processed by the CPU.
  • Sleep on overclocking: it can boost performance but risks instability and hardware damage; use CPU throttling for power/thermal management.
  • NVMe over PCIe provides significantly faster storage options for high-performance systems; NVMe requires compatible motherboards/slots.
  • ECC memory is important in error-sensitive environments (servers/workstations) for data integrity; nonparity/parity RAM is standard in consumer devices.
  • Safety must be prioritized: do not open PSUs; work with powered-down equipment and properly discharge capacitors.

Note on content gaps

  • Some topics (1.2 Safety Act, 1.4 Installation Procedures, 1.5 BIOS/UEFI Settings) are listed as objectives but detailed content is not included in the transcript provided. When studying, consult the full course materials or official manuals for those sections to ensure complete coverage.