Computer Hardware Quiz

International & Access Foundation Programmes

• This presentation is about computer science modules for the international and access foundation programmes.
• The specific module part covered is Networks: PC Internals, Storage, and Network Storage.
• The presenter is Dr. Nevan Bermingham.

PC Structure

• A computer is composed of input, processing, and output devices.
• Input components, such as keyboards and mouses, provide data to the computer.
• The processing unit, typically a processor chip, processes the data.
• Output components, such as monitors and printers, display the results.
• Storage devices, like hard drives and flash memory, store data.

Inside a PC

• Key internal components include the CPU, RAM, CPU cooler, graphics card, motherboard, 5.25" bays, 3.5" bays, and the PSU (power supply unit).
• The hard drive is also an important component.

Motherboard

• The motherboard is the main circuit board of the computer.
• Key components on a motherboard include DRAM memory slots, power connector, CPU heat sinks and mounting points for fans, CPU socket, Northbridge, Southbridge, ROM, PCI slots, hard drive slots, backup battery, AGP slot, and connectors for peripherals (audio, ethernet, serial, USB).

DDR Types

• Different DDR SDRAM versions (DDR, DDR2, DDR3, DDR4, DDR5) exist with different release dates, bus clock frequencies, voltages, transfer rates and prefetch burst times.
• DDR RAM is volatile memory, and it needs a constant electrical supply to work.

What is RAM?

• RAM (Random Access Memory) is used as temporary storage for active programs in a computer.
• RAM is volatile, meaning it loses its contents when the power is switched off.

CPU Cache

• A cache is a small location within the CPU which reduces data access time.
• It stores recent data making processing faster.
• Caches generally check caches at high speeds for the relevant information.

Motherboard Features

• VGA Connector: used to connect display devices.
• Local Peripheral Bus: used for add-ons (such as MPEG).
• Video Memory Expansion: graphics memory (VRAM), possibly as a daughter card plugged into the motherboard.
• RAMDAC: converts digital to analog signals used by the monitor.
• Video-In Socket: inputs video from other sources (like VCRs).
• SVGA Connector: connects to a monitor using a 15-pin plug.

POST (Power-On Self Test)

• The POST is a pre-operating system test of the components.
• It’s a crucial procedure during startup.
• Essential for verifying if the system operates correctly.
• It checks components such as RAM, keyboard, hard drive and video card.

Types of Storage

• Mechanical Hard Disk Drives (HDDs), such as ATA IDE and SCSI drives use magnetic polarity to store information.
• Solid State Drives (SSDs) use flash memory (NAND flash memory) instead, offering generally faster access times.
• Flash Drives (USB keys) also use flash memory for storage.
• Tape Drives are generally obsolete as a storage device.
• Optical Disk Drives such as CDs or DVDs.

Mechanical Hard Disk Drives

• A HDD has spinning platters with magnetic read/write heads.
• The size of HDDs, measured in terabytes, has increased over the years.

Solid State Disk

• An SSD has no moving parts like an HDD.
• SSDs use flash memory allowing quicker data access than HDDs.
• The price of an SSD is also generally higher than an equivalent HDD, offering quicker access speed in its entirety.

HDD & SSD Internal Architecture Diagrams

• Shows structure (platters with heads for HDDs, and flash memory for SSDs).

Optical Storage

• Optical storage (CDs and DVDs) stores data in pits and lands on a disc, using laser technology that can either burn or read the pits.

Making Disks Reliable

• RAID (Redundant Array of Independent Disks) is a solution technique.

RAID Levels

• Different RAID levels (0, 1, 10) offer different combinations of performance and data reliability, in an attempt to improve overall memory processing stability.
• RAID 0 increases read/write performance.
• RAID 1 mirrors for redundancy.
• RAID 10 features both mirroring and striping.

Network Attached Storage (NAS)

• NAS devices are servers whose primary task is file storage across a network.
• NAS does not handle processes such as emails or login authentication.
  • This is usually better for handling many users, high quantities of storage, and large file access.

Storage Area Network (SAN)

• SAN devices are for large scale storage.
• A SAN uses a network to improve storage operations without affecting standard network performance like the primary LAN.

Cloud Computing

• Cloud computing involves multiple networked hardware, software, and internet infrastructure.
• It's a service-based platform rather than traditional hardware based, with costs associated usually per usage, rather than an upfront purchase price.
• This hides the complexity and detail of the infrastructure, making it easier to use.
• It is also capable of handling large, simultaneous access to files.

Software-as-a-Service (SaaS)

• SaaS is a method of software delivery where users connect via the internet with web browsers to use it.
• SaaS includes platforms such as Office 365 and Google Docs.

Cloud Delivery Models

• SaaS (Software as a service) is a cloud service model where software and applications run over a network, requiring no local installation.
• PaaS (Platform as a service) is a cloud service model where clients get access to resources such as databases and web servers via the internet, typically through an API.
• IaaS (Infrastructure as a service) provides customers with virtualized access to computing resources such as servers and storage, often offering the option to install their own software.

Cloud Storage

• Cloud storage is online, remote storage accessed through the Internet.
• It handles backups and data security for clients.
• Several web companies offer cloud storage services.

Task: Network Storage

• This is a task to work on to research how FAT (File Allocation Table) storage works.

File Systems

• FAT and NTFS are mechanisms for organising data in a File System.
• NTFS is more recent, more flexible, efficient and robust than FAT.

Advantages of Cloud Computing

• Improved Performance: Cloud computing allows for greater use of memory within the device, as the system stores processes in a distributed manner.
• Reduced software costs: Usually cheaper than buying commercial software as access to the software is through online subscription/usage.
• Instant software updates: Usually the software is regularly maintained and updated by the provider.
• Unlimited storage: Cloud storage can be scaled to suit users demand without needing to purchase additional devices.

Challenges of Cloud Computing

• Security: More susceptible to hacking than on-site solutions.
• Legal Issues: Problems with jurisdiction for stored data.
• Market Dominance of big companies: Competition or dependency on large companies like Google or Microsoft.
• Trusting data to another entity: Data security is less certain in cloud-based storage environments compared to local storage.
• Internet Access required & speed: Services rely on internet connectivity, impacting performance if access is interrupted or slow.