Tech level 3 cyber security 2e, 2f, 2g

Learning Objectives All learners will have the opportunity to: understand and explain the role of: pipelines multi-core processors the registers found in a computer including the accumulator understand the difference between alternating current(AC) and direct current(DC) describe the internal and external power supply units which convert AC to DC current compare and contrast external power supply units define computer cooling devices.

Assessment outcomes 2d – The Internal components of a computer 2e – Internal and external Power Supply Units (PSUs) which convert power from Alternating Current to Direct Current 2f – Cooling Devices and their purpose

Pre-Reading Discussion The concept of parallel processing and pipelines in computers The purpose of pipelines in computers Registers in computers: CPU Registers Special Registers The accumulator The reasons for cooling computers Different methods of cooling computers

Power Supplies: AC v DC Current is the flow of ‘electrons’ – It is measures by amplitude. AC (Alternating current) describes the flow of charge that changes direction periodically. As a result, the voltage level also reverses along with the current. AC is used to deliver power to houses, office buildings, etc. DC (direct current) is the unidirectional flow or movement of electric charge carriers (which are usually electrons). The intensity of the current can vary with time, but the general direction of movement stays the same at all times. 

Power Supplies: AC v DC AC (Alternating Current) DC (Direct Current)

Computer Power Supplies: AC to DC conversion Computers represent everything with bits, and ordinarily this means one voltage range for a 0 and another voltage range for a 1. Therefore an ‘alternating current’ that cannot guarantee delivering set voltage ranges is not useful: “Digital devices deal with logic levels, you need a steady (DC) voltage to represent a 1 and another steady voltage to represent a 0. Power is used each time a level changes. AC is constantly changing, and is defined by a peak voltage and a frequency, so a single voltage reading is meaningless. For example a house outlet could be 140V one time then –30V, etc (120V outlet swings between –170V and 170V)” - http://www.sharkyforums.com/showthread.php?114244-Why-do-computers-need- DC-power

Different types of Power Supply AC – to – DC Supply: AT Power Supply ATX Power Supple ATX – 2 Power Supply Uninterruptable Power Supple Task: Find out what the 3 AC-DC PSU’s are used for. Find out what a UPS is used for.

Different Types of power supply resources How to pick the best PC power supply pcworld.com/article/2025425/how-to- pick-the-best-pc-power-supply.html Types of PC Power Supply ehow.com/about_5438750_types-pc- power-supply.html What is a power supply and what does it do? helpwithpcs.com/hardware/power- supply-basics-inc-pinouts.php

Graded Exercises Complete the graded exercises for today’s lesson. (Lesson 3 Folder) Everyone should complete the grade D questions. If you have answered a question in your notes circle the section and write the question above it in a different coloured pen.

Pre-Reading for lesson 4 Make pre-reading notes on the following topics: Resources The purpose of memory in computer systems Different types of Internal Hard Drive: SSD Magnetic Disk SATA PCIe How Internal Hard Drives work Different types of memory and chips: RAM DRAM SRAM ROM PROM EPROM EEPROM See URLs in Lesson 4 Folder