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Computer Hardware: Demolition Lab

  • Computer Model Type
    • Windows XP Professional 1-2CPU

During the demolition lab, we were able to observe the interior of a personal computer. The computer opened like a binder, and we immediately saw the main components, with the exception of the hidden processor. The parts that were visible upon opening where the CD Player, hard disk, power supply, motherboard, RAM, crystal, and the battery. Each component will be recorded below.

The Opened Computer


The Processor
  1. Model/Info
    • Intel Pentium 4
  2. What is a processor?
    • Also called CPU - Central Processing Unit
    • The computer's brain
    • Carries out instructions
    • Made of ALU(Arithmetic Logic Unit) and CU(Control Unit)
      • ALU - where arithmetic and logical operations are performed
      • CU - takes the information, decodes and executes them calling the ALU when necessary
  3. Where is the processor?
    • On the motherboard
    • Underneath a fan (The fan is on top of the heat sink)
    • Directly underneath a heat sink
The fan that is over the processor.
The Heat Sink

The processor acts as the brain of the computer. It's primary function is to do all of the computation presented in programs. It was found on the motherboard underneath a fan and the heat sink. Both the fan and the heat sink provides the role of cooling down the processor when it becomes too hot. The processor can execute billions of instructions per second, so it can easily become heated.

According to Wikipedia, a processor "is the hardware within a computer system which carries out the instructions of a computer program by performing the basic arithmetical, logical, and input/output operations of the system. The term has been in use in the computer industry at least since the early 1960s. The form, design, and implementation of CPUs have changed over the course of their history, but their fundamental operation remains much the same."


  1. Model/Info
    • MT 16Volt64AG-40BCA
    • 512MB
  2. What is a RAM?
    • Random Access Memory
    • Allows data to be accessed in any random order (Fast Access)
    • Provides temporary storage
  3. Where is the RAM?
    • On the motherboard
    • Next to the processor

RAM stands for Random Access Memory. It is the temporary storage location of memory. The processor is connected to the RAM by buses, where it can access the necessary information in order to complete various instructions. According to Wikipedia, RAM " is a form of computer data storage. A random-access device allows stored data to be accessed in very nearly the same amount of time for any storage location, so data can be accessed quickly in any random order. In contrast, other data storage media such as hard disks, CDs, DVDs and magnetic tape, as well as early primary memory types such as drum memory, read and write data only in a predetermined order, consecutively, because of mechanical design limitations. Therefore the time to access a given data location varies significantly depending on its physical location."

Random Access Memory
Close-up view of RAM

CD Player

  1. Model/Info
    • Labeled as Compact Disc (CD Drive)
  2. What is a CD Player?
    • Stored information on optical discs (recorded on a spiral track)
    • Read with laser from the inside to outside of the ring
  3. Where was the CD Player?
    • Next to the Hard Drive

According to Wikipedia, a Compact Disc "is an optical disc used to store digital data. It was originally developed to store and play back sound recordings only, but the format was later adapted for storage of data (CD-ROM), write-once audio and data storage (CD-R), rewritable media (CD-RW), Video Compact Discs (VCD), Super Video Compact Discs (SVCD), PhotoCD, PictureCD, CD-i, and Enhanced CD."

A CD player "has three major mechanical components : a drive motor, a lens system, and a tracking mechanism. The drive motor (also called spindle) rotates the disc between 200 and 500 revolutions per minute. The tracking mechanism moves the lens system along the spiral tracks in which information is encoded, and the lens reads the information using a laser beam, typically produced by a laser diode. The laser reads information by focusing a beam on the CD, which is reflected back to a sensor. The sensor detects changes in the beam, and interprets these changes to read the data. This data is processed, and eventually converted to sound using a digital-to-analog converter (DAC)."

The CD Player. A data transferring cable (Belt looking cable) and power cables are connected to it.

Power Supply

  1. Model/Info
    • 210 watts
  2. What is a power supply?
    • Deals with conversion of electricity
  3. Where was the power supply?
    • Next to the Motherboard

The power supply was located next to the motherboard. It converts the electricity that from the power outlet to a form that the computer can use. The Wikipedia article on power supply says that the it is a converter that changes the electric energy provided into another form. It usually has a set voltage level of the current it can supply to the load. The wire cables that were found in the computer were used to power the whole computer with a form of electricity from the power supply. The belt-looking cables were used for data transfer.

External part connecting to the power supply(The way the computer is getting energy)
The Power Supply (Inside)

Hard Disk

  1. Model/Info
    • 80GB
    • Seagate
  2. What is a hard disk?
    • Device that stores permanent information
  3. Where was the hard disk?
    • Next to the CD Player
    • Across from the power supply

The hard disk keeps permanent information such as programs and saved files stored in the computer. The hard drive"is a non-volatile, random-access, magnetic data storage device. Introduced by IBM in 1956, HDDs have been the dominant secondary storage device in general purpose computers since the early 1960s....An HDD consists of one or more rigid ("hard") rapidly rotating discs (platters) coated with magnetic material. Magnetic heads arranged on a moving actuator arm read and write data to the surfaces. The read-write heads are supported on a thin layer of air inside the enclosed disk unit with only tiny gaps between the heads and the disk surface." So, even small specks of dust may make the disk unreadable. In order to recover the information on a hard drive, it must be open in a sterile environment.

Untouched Hard Disk
Opened Hard Disk
Removing Hard Disk


  1. What does a motherboard do?
    • Communication with system components
    • The lines on the board are circuits, used for computation
  2. Where was the motherboard?
    • Next to the Powersupply
    • Across from the CD player

The motherboard holds the processor, RAM, crystal and battery. A mother board "is a printed circuit board (PCB) found in all modern computers which holds many of the crucial components of the system, such as the central processing unit (CPU) and memory, and provides connectors for other peripherals." It "provides the electrical connections by which the other components of the system communicate. Unlike a backplane, it also connects the central processing unit and hosts other subsystems and devices."

The Motherboard(The entire picture!)


  1. Model/Info
    • 2 present on the motherboard
    • Number: D143A4H and D2050J4H
  2. What does a crystal do?
    • Improves the speed of the motherboard
    • Sets the rate and timing
  3. Where was the crystal?
    • Both on the motherboard
    • One next to the power supply
    • One next to the RAM and Battery

Computer clock crystals "are small electronic devices used for timing and synchronization. Typically, they are made from a quartz crystal that is expanded and contracted at a specific resonant frequency. The oscillation (expansion and contraction) rate is determined by the shape/mass of the quartz crystal and is very precise. The "clock crystal" of a computer provides the timing mechanism that ensures that all of these calculations are synchronized and processed in the correct order. This synchronization allows all the various internal circuits of a computer to work in harmony."(From soyouwanna)

The Crystal #1
The Crystal #2


The Battery(Circle)
  1. Model/Info
    • +3V
  2. What does the battery do?
    • Keeps information, such as the date and the time
  3. Where was the battery?
    • On the motherboard
    • Next to the crystal

In the Wiki battery page, it states that "the memory and real-time clock are generally powered by a CR2032 lithium coin cell. These cells last two to ten years, depending on the type of motherboard, ambient temperature and the length of time that the system is powered off, while other common cell types can last significantly longer or shorter periods, such as the CR2016 which will generally last about 40% as long. Higher temperatures and longer power-off time will shorten cell life."