Main Parts of Personal Computer System Unit The System Unit: This is simply the box like case called the tower, which houses the motherboard, which houses the CPU. It also houses all the drives, such as the CD- ROM drive and the DVD-ROM drive. 1 2 3 1
Motherboard The system board (motherboard): The system board is found within your system unit, tower, and all the vital computer systems are plugged directly into this board. Even the hard disk is attached either directly or through cables. These boards are getting smaller as the components are becoming more integrated. 4 5 CPU 6 2
The CPU (Central Processing Unit): This is one of the most important components of the computer system. This determines the PC speed (MHz and GHz). The CPU performs all calculations when running applications RAM Random Access Memory (RAM): Random Access Memory is where the operating system is first loaded into when the PC is switched on and also where your applications are copied to when you start an application. When you create data, it is temporarily stored in RAM until it is saved. RAM is volatile, as soon as the PC is switched off, the data on it will be deleted. The more RAM you have the better. 7 8 9 3
USB Port Universal Serial Bus (USB): The USB is a relatively new item within the computer. Many USB sockets may be found at the back of the system unit, allowing you to plug in devices designed for USB. Devices may include printers, scanners and digital cameras. 10 11 Keyboard 12 4
The Keyboard: An input device. It allows you to type information into the PC. Nowadays, keyboards are often designed as to make Windows easier to use, with additional keys and features. Mouse The Mouse: An input device. When using an operating system such as Windows, the mouse is used to select drop down menus, point and click on items and carry out many tasks 13 14 15 5
CD-ROM CD-ROM: Most computers are supplied with a Compact Disc-Read Only Memory drive nowadays. The CD can hold as much data as 450 floppy disks and is very convenient to use and carry. 16 17 DVD Drive 18 6
DVD Drives: The Digital Versatile Disc drive is similar to the CD-ROM drive but allows you to use DVD s which can store much more data and allows for faster data transfer between the disc and PC which allows you to watch movies on your PC. A CD- ROM can store about 650MB whereas the DVD- ROM can handle GB s of data. Hard Disk Hard (Fixed) Disk: The main, large storage area of the PC. It is used to store the operating system, applications programs and data. It is much faster than CD or DVD ROM s and can hold much more data. It is found inside the tower. 19 20 21 7
Monitor The Monitor: An output device, on which we view our programs. It ranges in different inch sizes and if it is not of a good quality, it may damage your eyesight. Additional items or cards: Many extra components may be added to the PC, which has the advantage of making the PC upgradeable as newer and better hardware comes along. 22 23 24 8
Sound Card Sound cards and speakers: Many computers are now supplied with sound cards, which allow you to hear sound from your speakers when running multi media programs. When having suitable software you can also talk to the computer, record sounds and make the computer type words which you have said. Printers: An output device, used to print (give a hard copy of) of documents stored in electronic form, usually on physical print media such as paper. 25 26 27 9
Scanners: An input device, used to scan information into the computer. Pictures can then be edited. Recordable CD s: These are CDs which you can write on called Compact Disc-Recordable (CD-R). Computer Performance Learning what makes an impact on the computer s performance 28 29 30 10
CPU Clock speed: It governs how fast the CPU will run. The higher the clock speed, the faster the PC. Measured in megahertz (MHz). RAM size: The more memory you have, the faster the PC works for you. Hard Disk speed and storage: Hard Disks are also measured by their speed, the Disk Access Time, measured in milliseconds. The smaller the access time the better. Storage capacity is measured in Gigabytes. Free Hard Disk Space: Free space is essential for the smooth running of your PC. This space is needed by the operating system to run the programs, as it creates many temporary files. Multitasking considerations: This means that Windows can run more than one program at a time but the more the programs the slower each program will work. 31 32 33 11
De-Fragmenting Files: This operation may increase the speed of your PC. Files get broken up into separate pieces by time and the defragmentation process joins them back together again. 34 12