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1.1 Block Diagram

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1.2 Motherboard
Can you identify CPU, memory, system clock, I/O on the motherboard?

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1.3 CPU
A central processing unit (CPU) is the electronic circuitry within a computer that carries out the instructions of a computer program by performing the basic arithmetic, logical, control and input/output (I/O) operations specified by the instructions.

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1.3 CPU is the brain of a PC.
Which CPU is used in your PC?

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1.3 CPU and clock rate
CPU clock speed, or clock rate, is measured in Hertz — generally in gigahertz, or GHz. A CPU’s clock speed rate is a measure of how many clock cycles a CPU can perform per second. For example, a CPU with a clock rate of 1.8 GHz can perform 1,800,000,000 clock cycles per second.

CPU, speed and price:
Intel Core i7-4930K @ 3.40GHz | 13,058 | $1,527.00
Intel Core i7-5820K @ 3.30GHz | 12,979 | $389.99
Intel Core i7-3930K @ 3.20GHz | 12,033 | $610.75
Intel Core i7-4790K @ 4.00GHz | 11,184 | $334.99
Intel Core i7-6700K @ 4.00GHz | 10,981 | $339.99
AMD FX-9590 Eight-Core | 10,248 | $209.00
Intel Core i7-4770K @ 3.50GHz | 10,122 | $399.00
Intel Core i7-4790 @ 3.60GHz | 9,991 | $297.99
Intel Core i7-6700 @ 3.40GHz | 9,966 | $304.99
Intel Core i7-4770 @ 3.40GHz | 9,813 | $312.99
Intel Core i7-3770K @ 3.50GHz | 9,556 | $449.00
Intel Core i7-3770 @ 3.40GHz | 9,325 | $224.97
Intel Core i7-3820 @ 3.60GHz | 8,989 | $672.59
AMD FX-8350 Eight-Core | 8,939 | $149.99
Intel Core i7-2600K @ 3.40GHz | 8,499 | $429.00
Intel Core i7-2600 @ 3.40GHz | 8,240 | $406.54
Intel Core i7-4720HQ @ 2.60GHz | 8,040 | NA
AMD FX-8320 Eight-Core | 8,008 | $139.99
Intel Core i7-6700HQ @ 2.60GHz | 8,006 | $1,509.00*
Intel Core i7-4710HQ @ 2.50GHz | 7,825 | NA
Intel Core i5-6600K @ 3.50GHz | 7,779 | $239.99
Intel Core i7-4700HQ @ 2.40GHz | 7,752 | $383.00*
Intel Core i7-4700MQ @ 2.40GHz | 7,735 | $467.40*
Intel Core i5-4690K @ 3.50GHz | 7,687 | $239.99

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1.3 Clock cycle and machine cycle

Clock cycle
The speed of a computer processor, or CPU, is determined by the clock cycle, which is the amount of time between two pulses of an oscillator. Generally speaking, the higher number of pulses per second, the faster the computer processor will be able to process information. The clock speed is measured in Hz, typically either megahertz (MHz) or gigahertz (GHz). For example, a 4GHz processor performs 4,000,000,000 clock cycles per second.

1 GHz = 1,000 MHz = 1,000,000 kHz = 1,000,000,000 Hz

Computer processors can execute one or more instructions per clock cycle, depending on the type of processor. Early computer processors and slower processors can only execute one instruction per clock cycle, but faster, more advanced processors can execute multiple instructions per clock cycle, processing data more efficiently.

Machine cycle

The steps performed by the computer processor for each machine language instruction received. The machine cycle is a 4 process cycle that includes reading and interpreting the machine language, executing the code and then storing that code.

Question: Assuming an addition operation takes 4 machine cycles to process, how long does a PC equipped with a CPU of 1 GHz take to calculate 1+1?

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1.4 Memory
Three types of memories used in PC: Hard drive, RAM, ROM.

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1.4. Conventional hard drive

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Static hard drive (left) and conventional hard drive (right)

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1.4 Memory
Random-access memory (RAM) is a form of computer data storage. A random-access memory device allows data items to be read or written in almost the same amount of time irrespective of the physical location of data inside the memory.

Read-only memory (ROM) is a type of non-volatile memory used in computers and other electronic devices. Data stored in ROM can only be modified slowly, with difficulty, or not at all, so it is mainly used to store firmware (software that is closely tied to specific hardware and unlikely to need frequent updates) or application software in plug-in cartridges.

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1.5 I/O
In computing, input/output or I/O (or, informally, io or IO) is the communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system. Inputs are the signals or data received by the system and outputs are the signals or data sent from it.

Identify the I/O ports:

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1.6 Bus
In computer architecture, a bus (a contraction of the Latin omnibus) is a communication system that transfers data between components inside a computer, or between computers. This expression covers all related hardware components (wire, optical fiber, etc.) and software, including communication protocols.

•CPU – fetch & execute. 3 kinds of processes are math operations, move data,  make decisions and jump to a new set of instructions
• Buses - system by which information is moved between the blocks. Three bus system: data bus, address bus, and control bus.
• Memory – read & write data program (von Neumann architecture)
•I/O – connection to “outside world”
• System clock – synchronize processes

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1.6 Bus
Bus cables in the PC

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2.1 Startup

1. Loading PC logo / motherboard logo

2. Loading system settings and device drivers

3. Initialising registers

4. Performing power-on self-test (POST)

5. Loading operating system from hard drive into RAM

6. Handing over controls to operating system

7. Running Word / Photoshop etc.

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2.2 Introduction to Excel
Self learning on 12 tutorials
https://www.youtube.com/channel/UCdG1GHxF95MUruRtFLqq0MQ