System unit Performed by Bektasova P.S. Checked by Sultanova Zh.Zh.

What is it? System unit is a box-like case that contains electronic components with different functions All components work together to accomplish main function of a computer

Common components Motherboard Processor System clock Memory Expansion cards Ports Power supply Hard disk

Motherboard Main circuit board of the system unit Ties everything together in a computer Contains expansion slots, processor chips and memory slots Also called system board

Central Processing Unit (CPU) Interprets and carries out basic instructions that operate a computer Also called the processor

Central Processing Unit (CPU) Control unit (CU) Directs and coordinates operations in computer Arithmetic/ Logic unit (ALU) Perform arithmetic operation and logical operation Control the speed of the operation

System clock Controls timing of all computer operations Generates regular electronic pulses, or ticks, that set operating pace of components of system unit

Memory Temporary storage area for operating system, application programs, and data Consists of one or more chips on motherboard Each byte stored in unique address

Memory. Two types RAM (Random Access Memory) ROM (Read Only Memory) Memory used by computer to store data while working on the system ROM (Read Only Memory) It contains permanently recorded instructions, vital for starting up a computer

Expansion cards How are expansion cards used?

Ports Inlets and outlets that connect external devices to system unit mouse Inlets and outlets that connect external devices to system unit keyboard USB USB serial port printer (parallel port) speaker monitor microphone game port network telephone line out telephone line in FM reception svideo out cable TV

Serial ports Parallel ports Transmits one bit of data at a time. Connects slow-speed devices, such as mouse. Transmits more than one bit data at a time. Uses devices like printer.

Hard disk A part of a unit, often called a "disk drive,“ "hard drive," or "hard disk drive” Stores information Provides quick access to data

System unit is the HEART of the computer

Sources www.wikipedia.com www.slideshare.net