1100 Ch03: Advanced Computer Hardware

Electrical Power and Computer Circuits

• Voltage measures the energy needed to move charges, essential for computer circuit operation.
• Current refers to the flow of electrons; accurate voltage and current are critical for proper function.
• Power fluctuations include blackouts, brownouts, noise, spikes, and power surges, all of which can damage hardware and cause data loss.

Types of Power Fluctuations

• Blackout: Complete power loss caused by issues like blown fuses or downed lines.
• Brownout: Temporary voltage reduction below 80% of normal, often due to overloaded circuits.
• Noise: Interference from sources like generators, resulting in poor power quality.
• Spike: Sudden voltage increase exceeding normal levels, often caused by lightning or system restarts.
• Power Surge: Brief dramatic voltage increase, lasting nanoseconds, can damage equipment.

Protection Against Power Fluctuations

• Surge Protector: Diverts excess voltage to ground, rated by joules—higher ratings mean better protection.
• Uninterruptible Power Supply (UPS): Provides consistent power, protects against brownouts and blackouts, and can safely shut down systems.
• Standby Power Supply (SPS): Offers backup power when voltage drops, but switching delays may decrease reliability.

CPU and Instruction Sets

• A program consists of sequenced instructions executed by a CPU using specific instruction sets.
• RISC (Reduced Instruction Set Computer): Focuses on a small set of instructions for rapid execution, exemplified by PowerPC and ARM CPUs.
• CISC (Complex Instruction Set Computer): Utilizes a broad instruction set, reducing processing steps, with examples like Intel x86 and Motorola 68k.

CPU Performance Enhancements

• Cache: High-speed memory storing frequently accessed data. It includes three levels:
  • L1 Cache: Fastest, directly on the CPU core (128 KB to 2 MB).
• Hyper-Threading (Intel): Allows simultaneous execution of multiple threads, enhancing performance.
• HyperTransport (AMD): Facilitates high-speed communication between the CPU and Northbridge chip.

CPU Metrics

• Speed measured in MHz (million cycles/s) or GHz (billion cycles/s).
• Processing capability depends on the Front Side Bus (FSB) width, often 32-bit or 64-bit.
• Overclocking: Running the CPU faster than specifications; risky and can cause damage.
• CPU Throttling: Operating below rated speed to conserve power, commonly used in mobile devices.

Multicore Processors

• Feature multiple cores on one chip, allowing for parallel processing and improved multitasking performance.
• Key Components:
  • Cores: Handle tasks independently for efficiency.
  • Cache Memory: Stores frequent data for quick access.

Storage Solutions: RAID

• RAID 10: Combines mirroring and striping for performance and redundancy, requiring a minimum of four drives.

Legacy Ports

• Legacy ports are older types of connections, largely replaced by newer technologies like USB.
• Types:
  • Serial Ports: Connect peripherals; available in 9-pin and 25-pin.
  • Parallel Ports: Send multiple bits simultaneously; often called printer ports.
  • Game Ports: 15-pin connectors for joysticks, historically found on dedicated expansion cards.
  • PS/2 Ports: Connect keyboards and mice with color-coded connectors.
  • Audio Ports: Connect external audio devices.
  • VGA Ports: Oldest graphics port for monitors, now mostly legacy.
  • DVI Ports: Designed for transmitting uncompressed digital video.

Responsible Disposal of Computer Parts

• Functioning parts should be donated or sold; non-functional parts require proper disposal.
• Hazardous Waste: Batteries contain harmful metals like mercury; recycling is crucial.
• Monitors: CRT monitors hold high voltage and toxic materials; must be disposed of safely.
• Printer Cartridges: Can be recycled or refilled but may void warranties if mishandled.
• Chemicals and Solvents: Dispose of properly; never down the sink or drain.