Pesonal systems
- 2. WHAT IS A COMPUTER? A computer is an electronic machine that performs calculations based on a set of instructions. The first computers were huge, room-sized machines that took teams of people to build, manage, and maintain.
- 5. COMPUTER SYSTEM CONSIST OF HARDWARE SOFTWARE is the physical equipment. It includes the case, keyboard, monitor, cables, storage drives, speakers, and printers. includes the operating system and programs. > Operating system manages computer operations such as identifying, accessing, and processing information. >Programs or applications perform different functions.
- 7. Personal computer systems (PCs) are made up of hardware and software components that must be chosen with specific features in mind. All the components must be compatible to work as a system.
- 8. Computer cases are the enclosures that house the internal computer components including the power supply. They come in different sizes, also known as form factor.
- 9. CASES Cases are typically made of plastic, steel, or aluminum and provide the framework to support, protect, and cool the internal components. A device form factor refers to its physical design and look. Desktop computers are available in a variety of form factors. These types include:
- 10. Horizontal case - These were popular with early computer systems. The computer case was horizontally oriented on the user’s desk with the monitor positioned on top. This form factor is no longer popular.
- 11. Full-size tower — this is a computer case that is oriented vertically. It is typically located on the floor under or beside a desk or table. It provides room for expansion to accommodate additional components such as disk drives, adapter cards, and more. It requires an external keyboard, mouse, and monitor.
- 12. Compact tower — this is a smaller version of the full-size tower and is commonly found in the corporate environment. It may also be called a mini-tower or small form factor (SFF) model. It can be located on the user’s desk or on the floor. It provides limited room for expansion. It requires an external keyboard, mouse, and monitor.
- 13. All-in-one — all of the computer system components are integrated into the display. They often include touchscreen input and built-in microphone and speakers. Depending on the model, all-in- one computers offer little to no expansion capabilities. It requires an external keyboard, mouse, and power source.
- 14. Power Supplies Electricity from wall outlets is provided in alternating current (AC). However, all components inside a computer require direct current (DC) power. To obtain DC power, computers use a power supply,
- 15. Advanced Technology (AT) - this is the original power supply for legacy computer systems now considered obsolete.
- 16. AT Extended (ATX) —This is the updated version of the AT, but it is still considered to be obsolete.
- 17. ATX12V —This is the most common power supply on the market today. It includes a second motherboard connector to provide dedicated power to the CPU. There are several versions of ATX12V available.
- 18. EPS12V —This was originally designed for network servers but is now commonly used in high- end desktop models.
- 19. These connectors are used to power various internal components such as the motherboard and disk drives. The connectors are keyed which means that they are designed to be inserted in only one orientation. Common power supply connectors include the following:
- 20. A Molex keyed connector —connects to optical drives, hard drives, or other devices that use older technology.
- 21. SATA keyed connector —connects to an optical drive or a hard drive. The SATA connector is wider and thinner than a Molex connector.
- 22. Berg keyed connector —connects to a legacy floppy drive. A Berg connector is smaller than a Molex connector.
- 23. 20-pin or 24-pin slotted connector —connects to the motherboard. The 24-pin connector has two rows of 12 pins each, and the 20-pin connector has two rows of 10 pins each.
- 24. four-pin to eight- pin auxiliary power connector —two rows of two or four pins; supplies power to all areas of the motherboard. The auxiliary power connector is the same shape as the main power connector but smaller. It can also power other devices within the computer.
- 25. 6/8-pin PCIe power connector —two rows of three or four pins; supplies power to other internal components.
- 26. Voltage is a measure of work required to move a charge from one location to another. Voltage is measured in volts (V). Current is a measure of the amount of electrons moving through a circuit. Current is measured in amperes, or amps (A).
- 27. Resistance refers to the opposition to the flow of current in a circuit. Lower resistance allows more current, and therefore more power, to flow through a circuit. Resistance is measured in ohms. Power is a measure of the pressure required to push electrons through a circuit (voltage), multiplied by the number of electrons going through that circuit (current). The measurement is called watts (W)
- 29. Motherboard also known as the system board or the main board, is the backbone of the computer. A motherboard is a printed circuit board (PCB) that contains buses, or electrical pathways, that interconnect electronic components.
- 31. Central Processing Unit (CPU) -This is considered the brain of the computer. Random Access Memory (RAM)—Thisis a temporary location to store data and applications.
- 32. Expansion slots —to provide locations to connect additional components
- 33. Basic input/outputsystem (BIOS) chip and Unified Extensible Firmware Interface (UEFI) .—used to help boot the computer and to manage the flow of data between the hard drive, video card, keyboard, mouse, and more. Recently, the BIOS has been enhanced by UEFI. UEFI specifies a different software interface for boot and runtime services but still relies on the traditional BIOS for system configuration, power-on self-test (POST), and setup.
- 34. Chipset —consists of the integrated circuits on the motherboard that control how system hardware interacts with the CPU and motherboard. It also establishes how much memory can be added to a motherboard and the type of connectors on the motherboard.
- 35. Most chipsets consist of the following two types:
- 36. Northbridge —controls high speed access to the RAM and video card. It also controls the speed at which the CPU communicates with all of the other
- 37. Southbridge - Helps CPU to communicate with slower-speed devices including hard drives, Universal Serial Bus (USB) ports, and expansion slots.