SECTION 1 – Systems Technologies
1.1 CPU & Processing
CPU = the computer’s brain.
● ALU (Arithmetic Logic Unit): performs maths and logic
● CU (Control Unit): directs data flow
● Registers: tiny, super-fast storage inside the CPU
● Machine cycle: Fetch → Decode → Execute → Store
Performance factors:
● Clock speed (GHz): higher = faster
● System clock: synchronises all components; CPU speed is a multiple of this
● Cores: each core = a separate processor (dual = 2, quad = 4, etc.)
● Hyper-threading: 1 core handles 2 threads simultaneously → better multitasking
● Multitasking: running multiple applications at once
● Multithreading: splitting one program into multiple tasks/threads
● Parallel processing: multiple CPUs/cores working together
Overclocking: running CPU faster than designed
● Pros: faster performance
● Cons: more heat, higher power use, shorter lifespan, may void warranty
● Methods: increase clock multiplier, raise bus speed, adjust voltage (BIOS/UEFI)
Underclocking: running CPU slower
● Pros: saves power, reduces heat, extends lifespan
Cooling methods:
● Fans: standard air cooling
● Heat sinks: metal fins absorb heat
● Liquid cooling: efficient but expensive
Other performance factors:
● Bus width: data transferred per cycle
● Cache size: bigger = faster processing
● Word size: number of bits CPU processes in one step (32-bit, 64-bit)
, 1.2 Memory
● RAM (Random Access Memory): temporary, volatile, used by active programs
○ DRAM: slower, cheaper, needs refreshing
○ SRAM: faster, used for cache
○ Cache: very fast, stores frequently used data
● ROM (Read-Only Memory): permanent, non-volatile, stores BIOS/UEFI
● Virtual memory: part of hard drive used as pretend RAM (slower than real RAM)
● VRAM (Video RAM): memory for GPU; stores textures, images, frame buffers (more
VRAM = better graphics performance)
1.3 BIOS & UEFI
● BIOS (Basic Input/Output System): old firmware, loads OS from storage
● UEFI (Unified Extensible Firmware Interface): modern replacement, faster startup,
supports large drives, graphical interface
1.4 Storage
● HDD (Hard Disk Drive): mechanical, cheap, large capacity, slower
● SSD (Solid State Drive): no moving parts, very fast, more expensive
● Hybrid (SSHD): HDD + small SSD cache
● Optical storage: CDs, DVDs, Blu-ray
● Flash storage: USB sticks, SD cards
HDD vs SSD:
● HDD: slower, cheaper, mechanical
● SSD: faster, durable, but costly per GB
RAID (Redundant Array of Independent Disks):
● RAID 0: striping (fast, no backup)
● RAID 1: mirroring (duplicate data, safe but costly)
● RAID 5: striping + parity (balance of speed & redundancy)
1.5 Graphics Processing
● GPU (Graphics Processing Unit): specialised processor for graphics, AI, parallel
calculations
● VRAM: dedicated GPU memory, stores textures & rendering data
1.1 CPU & Processing
CPU = the computer’s brain.
● ALU (Arithmetic Logic Unit): performs maths and logic
● CU (Control Unit): directs data flow
● Registers: tiny, super-fast storage inside the CPU
● Machine cycle: Fetch → Decode → Execute → Store
Performance factors:
● Clock speed (GHz): higher = faster
● System clock: synchronises all components; CPU speed is a multiple of this
● Cores: each core = a separate processor (dual = 2, quad = 4, etc.)
● Hyper-threading: 1 core handles 2 threads simultaneously → better multitasking
● Multitasking: running multiple applications at once
● Multithreading: splitting one program into multiple tasks/threads
● Parallel processing: multiple CPUs/cores working together
Overclocking: running CPU faster than designed
● Pros: faster performance
● Cons: more heat, higher power use, shorter lifespan, may void warranty
● Methods: increase clock multiplier, raise bus speed, adjust voltage (BIOS/UEFI)
Underclocking: running CPU slower
● Pros: saves power, reduces heat, extends lifespan
Cooling methods:
● Fans: standard air cooling
● Heat sinks: metal fins absorb heat
● Liquid cooling: efficient but expensive
Other performance factors:
● Bus width: data transferred per cycle
● Cache size: bigger = faster processing
● Word size: number of bits CPU processes in one step (32-bit, 64-bit)
, 1.2 Memory
● RAM (Random Access Memory): temporary, volatile, used by active programs
○ DRAM: slower, cheaper, needs refreshing
○ SRAM: faster, used for cache
○ Cache: very fast, stores frequently used data
● ROM (Read-Only Memory): permanent, non-volatile, stores BIOS/UEFI
● Virtual memory: part of hard drive used as pretend RAM (slower than real RAM)
● VRAM (Video RAM): memory for GPU; stores textures, images, frame buffers (more
VRAM = better graphics performance)
1.3 BIOS & UEFI
● BIOS (Basic Input/Output System): old firmware, loads OS from storage
● UEFI (Unified Extensible Firmware Interface): modern replacement, faster startup,
supports large drives, graphical interface
1.4 Storage
● HDD (Hard Disk Drive): mechanical, cheap, large capacity, slower
● SSD (Solid State Drive): no moving parts, very fast, more expensive
● Hybrid (SSHD): HDD + small SSD cache
● Optical storage: CDs, DVDs, Blu-ray
● Flash storage: USB sticks, SD cards
HDD vs SSD:
● HDD: slower, cheaper, mechanical
● SSD: faster, durable, but costly per GB
RAID (Redundant Array of Independent Disks):
● RAID 0: striping (fast, no backup)
● RAID 1: mirroring (duplicate data, safe but costly)
● RAID 5: striping + parity (balance of speed & redundancy)
1.5 Graphics Processing
● GPU (Graphics Processing Unit): specialised processor for graphics, AI, parallel
calculations
● VRAM: dedicated GPU memory, stores textures & rendering data
