2.5 HARDWARE (2.2.1 - 2.5.3)
(2.2.1 - 2.5.3)
Adapter Card Slot
• Slots on the motherboard that hold adapter
• Adapter card slots are also called expansion
– Specifically designed to connect graphic adapters.
– To connect devices such as network cards, sound
cards, modems, extra ports such as USB or serial
TV tuner cards and disk controllers.
Main circuit board of the system unit.
• The functions of the motherboard:
– Holds various components of the system.
– Provides connectors for other peripherals.
BIOS chip and battery
• Slots on the motherboard that hold memory
• Memory module is a small circuit board that
holds RAM chips
• A slot on the motherboard that holds a
An electronic component that interprets and
carries out the basic instructions that operate
• Also called Central Processing Unit (CPU)
• A component of the processor that directs and
coordinates most of the operations in the
computer.Interprets each instruction of a program, and
then initiates the appropriate action to carry
out the instruction
Arithmetic Logic Unit
• A component of the processor that performs
arithmetic, comparison and other operations.
– Arithmetic operations are +, -, *, /
– Comparison operations are > , >=, <, <=, =,
A set of four basic steps performed by a
processor every time it executes one
- Control unit fetches the instruction
and data from memory.
- Control unit interprets the
instruction and sends the instruction and
data to the ALU.
- ALU performs calculations on the
- The results of the calculations are
stored in the memory
Consists of electronic components that store
instructions waiting to be executed by the
processor, data needed by those instructions,
and the results of processing the data.
Random Access Memory(RAM)
• Memory chips that holds data or programs
that are currently being used by the processor
• Can be read from and written to by the
- loses its contents when the power is
DRAM (Dynamic RAM)
- Chips must be reenergized
constantly to keep their contents.
SRAM (Static RAM)
- Do not have to be reenergized
as often as DRAM chips, faster access time,
more reliable but more expensive than DRAM.
MRAM (Magnetoresistive RAM)
- Stores data
using magnetic charges instead of electrical charges,
greater storage capacity, consume less energy, faster
access time, more expensive, and non-volatile.
Read Only Memory(ROM)
• Memory chips that stores permanent data or
instructions needed by a computer or devices.
• Can be read from, but cannot be written to by
• Non volatile – does not lose its contents when
the power is turned off.
PROM (Programmable ROM)
- A blank ROM chip
which a programmer can write permanently; once
written, the contents cannot be erased or changed
EPROM (Erasable Programmable ROM
Allows the programmer to erase the contents by
exposing to ultraviolet light.
EEPROM (Electrically Erasable Programmable
- Allows the programmer to erase the
contents with an electric signal.