tnx

1. COMPUTER HARDWARE

2. Tentative Content
• Basic units of computer hardware
• basic function of CPU
• Memory units
• I/O Devices
• peripheral devices
• Bus Architecture
• Storage devices: Basic function of HDD, CD-
ROM.

3. THE PARTS OF A COMPUTER
SYSTEM
• Hardware
• Software
• Data
• Users

5. HARDWARE
• A computer's hardware consists of
electronic devices; the parts you can see
and touch.
• The term "device" refers to any piece of
hardware used by the computer, such as
a keyboard, monitor, modem, mouse, etc

7. Software
Software –is the collection of program and other
associated documents that helps to control, manage
and integrate the components of computer system to
accomplish a specific task.
Data
• Data consists of raw facts, which the computer can
manipulate and process into information.
• Computerized data is digital, meaning that it has been
reduced to digits, or numbers. The computer stores
and reads all data as numbers.
• Although computers use data in digital form, they
convert data into forms that people can understand,
such as text, numerals, sounds, and images
User

8. COMPUTER HARDWARE
OVERVIEW
The Basics When Purchasing
• Motherboard
• Microprocessor or CPU
• Computer Memory (RAM)
• Hard Disk Drive
• CD/DVD Drives
• Video Card
• Monitor
• Modem
• Network Devices
Additional Purchasing Decisions
• Printers
• Air Conditioner
• UPS

9. MOTHERBOARD
The Motherboard
The mother for your:
- Microprocessor Chip or Chips
- Memory Chips
- For the other internal components that enable your system to function
Can be detrimental to:
- Overall Microprocessor speed
- Scalability

10. MOTHERBOARD
The Motherboard
PCI Slots –
(Peripheral Component Interconnect)
Normally used for other devices
Such as a sound card, modem,
or a network interface card.
operates at 33MHz and has a
maximum bandwidth of 133MB/s.
ISA Slots –
(Industry Standard Architecture )
Not used very often with modern
Motherboards. The PCI Bus was
its replacement. operates at
16MHz and has a maximum
bandwidth of 16MB/s.
CMOS – Complementary metal–
oxide–semiconductor
used to store important system
information and configuration
settings while the computer is off

12. (Video Graphics Array)

13. MICROPROCESSOR OR CPU
The Microprocessor
Buried somewhere on that big motherboard is a specific chip that controls your
entire computer system.
This chip is called a microprocessor or a central processing unit (CPU).
The Microprocessor is responsible for:
- processes all the instructions necessary for your computer to perform its duties
- running the computer system with speed and efficiency

14. MICROPROCESSORS: TECH
SPECS
The Microprocessor
- CPU speed is measured in megahertz (MHz)
- Shopping for a new PC, look for one with the combination of a powerful
microprocessor and a high clock speed for best performance.
- Today's fastest chips are actually measured in Gigahertz (GHz)
How fast is 1 Gigahertz?
1000 MHZ, or one billion cycles per second!

15. MICROPROCESSORS: TECH
SPECS
Many confusing specifications often are quoted in discussions of processors
Specifications may include but are not limited to:
- data bus
- speed
Processors can be identified by two main parameters: how wide they are and
how fast they are
Data Bus
This defines the rate at which data can be moved into or out of the processor
Speed
Refers to the clock speed of the Microprocessor in MHz or GHz
Additional Term:
HT – Stands for Hyper Threading Technology

16. COMPUTER MEMORY: (RAM)
Before your CPU can process any instructions you give it, those instructions must
be stored somewhere, in preparation for access by the microprocessor
- The more memory that is available in a machine, the more instructions and data
that can be stored at one time.
- If the computer does not have enough RAM to run an application than pieces of
the running application will be stored on the Hard Drive temporarily in a method
known as “Virtual Memory” and the CPU will then have to retrieve information
from the virtual memory causing a bottleneck in the system.
RAM is measured in bytes:
For example, a computer with 256MB RAM has approximately 256 million bytes of
memory that programs can use.

17. COMPUTER MEMORY: (RAM)
RAM Types:
DRAM - Pronounced dee-ram, DRAM stands for dynamic random access
memory, a type of memory used in most personal computers.
SDRAM - Short for Synchronous DRAM, a type of DRAM that can run at much
higher clock speeds than conventional memory. SDRAM actually synchronizes
itself with the CPU's bus and is capable of running at 133 MHz, about three times
faster than conventional RAM
DDR SDRAM - Short for Double Data Rate-Synchronous DRAM, a type of
SDRAM that supports data transfers on both edges of each clock cycle (the rising
and falling edges), effectively doubling the memory chip's data throughput. DDR-
SDRAM also consumes less power
Additional Terms:
DIMM - Short for dual in-line memory module, DIMM has 64-bit path. The Pentium
processor requires a 64-bit path to memory thus you can install DIMMs one or two at a time
if you wish.
SIMM - Short for single in-line memory module, SIMM has 32-bit path. You must install
SIMMs two at a time to stay consistent with 64 bits.

18. HARD DISK DRIVES: LONG-TERM
STORAGE
The hard disk permanently stores all your important data. Some hard disks can
store more than 100 gigabytes of data.
RPM – Determines how fast your Hard Drive will access data.
Revolutions Per Minute.
Typical RPM Values:
Desktop Machine – 7,200 RPM
Laptop Machines – 5,000 RPM
Server Machines – 10,000 RPM

20. HARD DISK DRIVES: LONG-TERM
STORAGE
Additional Terms:
ATA – Advanced Technology Attachment
Serial ATA - an evolution of the Parallel ATA physical storage interface. Transfer
rates for Serial ATA begin at 150MBps.
SCSI - Short for small computer system interface. Pronounced "scuzzy," SCSI
is a parallel interface standard used by Apple Macintosh computers, PCs, and
many UNIX systems for attaching peripheral devices to computers.
SCSI Devices offer the following benefits:
- SCSI interfaces provide for faster data transmission rates (up to 80
megabytes per second) than standard serial and parallel ports.
- You can attach many devices to a single SCSI port, so that SCSI is really an
I/O bus rather than simply an interface

21. FACTORS AFFECTING PROCESSING
SPEED
• Registers
• RAM
• The System Clock
• The Bus
• Cache Memory:

22. FACTORS AFFECTING PROCESSING SPEED –REGISTERS
• The CPU contains a number of small memory areas,
called registers, which store data and instructions while
the CPU processes them.
• The size of the registers (also called word size)
determines the amount of data with which the computer
can work at a one time.
• Today, most PCs have 32-bit registers, mean the CPU
can process four bytes of data at one time. Register
sizes are rapidly growing to 64 bits.

23. FACTORS AFFECTING PROCESSING SPEED –RAM
• The amount of RAM in a PC has a direct affect on the
system's speed.
• The more RAM a PC has, the more program instructions
and data can be held in memory, which is faster than
storage on disk.
• If a PC does not have enough memory to run a program,
it must move data between RAM and the hard disk
frequently. This process, called swapping, can greatly
slow a PC's performance.

26. FACTORS AFFECTING PROCESSING SPEED –THE SYSTEM CLOCK
• The computer's system clock sets the pace for the CPU
by using a vibrating quartz crystal.
• A single "tick" of the clock is the time required to turn a
transistor off and back on. This is called a clock cycle.
• Clock cycles are measured in Hertz (Hz), a measure of
cycles per second. If a computer has a clock speed of
300 MHz, then its system clock "ticks" 300 million times
every second.
• The faster a PC's clock runs, the more instructions the
PC can execute each second.

27. FACTORS AFFECTING PROCESSING SPEED –THE BUS
• A bus is a path between the components of a computer.
Data and instructions travel along these paths.
• The data bus' width determines how many bits can be
transmitted between the CPU and other devices.
• The address bus runs only between the CPU and RAM,
and carries nothing but memory addresses for the CPU
to use.
• Peripheral devices are connected to the CPU by an
expansion bus.

29. ORS AFFECTING PROCESSING SPEED –CACHE MEMORY
• Cache memory is high-speed memory that holds the
most recent data and instructions that have been
loaded by the CPU.
• Cache is located directly on the CPU or between the
CPU and RAM, making it faster than normal RAM.
• CPU-resident cache is called Level-1 (L1) cache.
External cache is called Level-2 (L2) cache.
• The amount of cache memory has a tremendous impact
on the computer's speed.

31. CD DRIVES
Information on a CD-ROM is encoded in the form of microscopic pits (representing
the 1s and 0s of computer binary language) below the disc's surface.
- Multiples of 150kb per second so 24x is writing at 3600kb per second or 3.6
MB per second.

32. MONITORS
Operating a computer would be difficult if you didn't constantly receive visual
feedback showing you what your machine is doing. This vital function is provided by
your computer's monitor.
DP (dot pitch) - Also called phosphor pitch, a measurement that indicates the
diagonal distance between like-colored phosphor dots on a display screen.
- the dot pitch is one of the principal characteristics that determine the quality of
display monitors.
- The lower the number, the crisper the image. The dot pitch of color monitors
for personal computers ranges from about 0.15 mm to 0.30 mm
Additional Terms:
CRT – Cathode Ray Tube, the technology used in most
televisions
LCD – Liquid Crystal Display, a type of display used
in digital watches and many portable computers

33. VIDEO CARDS
A board that plugs into a personal computer AGP Port on the motherboard to give it
display capabilities.
- Modern video adapters contain memory, so that the computer's RAM is not used
for storing displays.
- Modern adapters have their own graphics
coprocessor for performing graphics
calculations. These adapters are often
called graphics accelerators.

34. MODEMS: GETTING CONNECTED
Almost all PC systems today include a modem. A modem enables your computer to
connect to a telephone or cable line and transmit data to and from the Internet.
- Modems come in either internal (card-based) or external models that hook up to
an open port on the back of your system.
The following characteristics distinguish one modem from another:
bps - How fast the modem can transmit and receive data. The fastest
modems run at 57,600 bps.
voice/data - Many modems support a switch to change between voice and
data modes. In data mode, the modem acts like a regular modem. In voice
mode, the modem acts like a regular telephone.
data compression - Some modems perform data compression, which
enables them to send data at faster rates.
Fax capability - Most modern modems are fax modems, which means that
they can send and receive faxes

35. NIC
The most common type of network is a wired network using Ethernet cables and
hardware. For this type of network, you need to install and configure a network
interface card (NIC) in each of your PCs.

36. PRINTERS
3 Selling Points:
* All in one features (i.e. scanning, printing, faxing)
* Standalone capabilities
* Resolution
Resolution - Refers to the sharpness and clarity of an image. 300dpi (dots per
inch) For example, a 300-dpi (dots per inch) printer is one that is capable of printing
300 distinct dots in a line 1 inch long. This means it can print 90,000 dots per
square inch.
Screen Resolution - the screen resolution signifies the number of dots (pixels)
on the entire screen. For example, a 640-by-480 pixel screen is capable of
displaying 640 distinct dots on each of 480 lines, or about 300,000 pixels.
PPM (Page Per Minute) - Stands for pages per minute and is used to
measure the speed of certain types of printers Also take note that typically
this measurement is for Text and NOT graphics.

37. AIR CONDITIONER
Keep the equipment cool!
- look at the BTU readings, in most situations at least 5,000 BTU is required

38. UPS
uninterruptible power supply, a power supply that includes a battery to maintain
power in the event of a power outage.
Typically, a UPS keeps a computer running for several minutes after a power
outage, enabling you to save data that is in RAM and shut down the computer
gracefully
There are two basic types of UPS:
- standby power systems (SPSs) - SPS
monitors the power line and switches to
battery power as soon as it detects a
problem.
- on-line UPS systems – provides constant
power from its own converter.

39. RAID DEVICES
A category of disk drives that employ two or more drives in combination for fault
tolerance and performance. RAID disk drives are used frequently on servers but
aren't generally necessary for personal computers.
- There are number of different RAID levels. The three most common are 0 and 5
0 - Provides data striping (spreading out blocks of each file across multiple
disks) but no redundancy. This improves performance but does not deliver
fault tolerance.
5 - Provides data striping at the byte
level and also stripe error correction
information. This results in excellent
performance and good fault
tolerance.