The Components of the System Unit

1. The Components of the System Unit By: Clara Miles and JarrickLumma

2. The Motherboard • The motherboard is the main circuit board of the system unit. It can also be called a system board. • It contains places to attach to many components, such as CPU, memory, hard drive, controller, graphics card, sound card, keyboard, and mouse. • The motherboard’s most basic role is to connect the system’s microprocessor to the rest of the computer.

3. The Processor • A processor is a logic circuitry that responds to and processes the basic rules that drive a computer. • The processor interprets and carries out the instructions that operate a computer. It manages most of a computer’s operations. • The processor contains a control unit and an arithmetic logic unit. They work together to perform many operations with processing. • It is commonly said to be the “brain” of the computer.

4. The Control Unit • The control unit is the component of the processor that directs most of the operations in the computer. It plays a big role to the processor. • The control unit interprets each instruction issued by a program and then initiates the appropriate action to carry out the instruction.

5. The Arithmetic Logic Unit • The arithmetic logic unit (ALU), is another component of the processor. It performs arithmetic, comparison, and other operations. • Arithmetic operations include basic calculations such as addition, subtraction, multiplication, and division. • Comparison operations involve comparing one data item with another to determine whether the first item is greater than, equal to, or less than the other item. • The arithmetic logic unit is the building block of the central processing unit of a computer.

6. Machine Cycle • A machine cycle, also called a processor cycle or an instruction cycle, is the basic operation performed by a central processing unit. • It consists of a sequence of four steps. They are fetch, decode, execute, and if necessary, storing. • For every instruction, a processor repeats those four basic operations, which comprise a machine cycle.

7. Registers • High speed storage locations that are located in a processor. • Temporarily hold data and instructions. • Are part of the processer and not memory or a permanent storage device. • Processers have many different types of registers

8. How Registers Function • Register functions include storing the location from where an instruction was fetched. • Storing an instruction while the control unit decodes it. • Storing data while the ALU computes it. • Storing the results of a calculation.

9. The System Clock • A small quartz crystal unit that controls the timing of all computer operations. • It generates a regular electronic pulse, or tick, that set the operating speed of the system unit. • Each tick equals one clock cycle. • The pace of the system clock is called clock speed. The higher the clock speed the higher the more instruction to processer can execute per second. • Measured in gigahertz.

10. Comparison of Personal Computer Processors • Leading processor chip manufactures for PCs: Intel, AMD, Transmeta, IBM, and Motorola. • When you compare you look at the brand, how fast the system clock is, what the core of the processor is, and if the processor is a chip.

11. Heat Sinks, Heat Pipes, and Liquid Cooling • Heat sink- a small ceramic or metal component with fins on it surface that absorbs and disperses heat produced by the electric components inside. • Heat Pipes- smaller than heat sink and cools processors in notebooks. • Liquid cooling- uses continuous flow of liquids, such as water and glycol, in process that transfers the heated fluid away from the processor to a radiator grill that cools the liquid and returns it to the processor.

12. Parallel Processing • A method that uses multiple processors simultaneously to execute one task or program. • It divides a single task into portions. • Some PCs use this method with dual-core or multicore processors. • It is used by supercomputers.