103b ag 2012f

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PC Demolition Lab

This lab is an assignment for CSC 103 at Smith College. Other student wikis for this class can be found here.

Overview

103ag overview.jpg
  • The PC taken apart was a Dell DCNE.
  • When the cover was removed, the following parts were visible:
    • Motherboard
    • Memory
    • Power supply
    • Fan
    • CD/DVD drive



Motherboard

103ag motherboard.jpg
  • According to Wikipedia, the motherboard "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 holds the microprocessor, allowing various components to connect to it. The lines on the motherboard are the circuits. (in Wikipedia, retrieved on Oct. 10 2012, from http://en.wikipedia.org/wiki/Motherboard)
  • A small battery can be found on the motherboard. Its function is to maintain the system time even when the computer is not running.



Processor

  • Intel Pentium (model number unreadable)
103ag microprocessor.jpg
  • According to Wikipedia, the microprocessor is a "programmable device that (1) accepts digital data as input, (2) processes it according to instructions stored in its memory, and (3) provides results as output." It contains the CPU, which is the piece of hardware that "performs arithmetic and logical operations." It is located directly below the fan, which helps cool down the processor when it heats up due to the billions of instructions it carries out per second (in Wikipedia, retrieved on Oct. 10 2012, from http://en.wikipedia.org/wiki/Microprocessor). According to the article How Microprocessors Work," the microprocessor is made up of millions of transistors (on/off switches), which are etched onto an integrated circuit (a thin piece of silicon) (in How Stuff Works, retrieved on Oct. 10 2012, from http://computer.howstuffworks.com/microprocessor1.htm).
  • Also on the motherboard is an oscillator crystal, which regulates the microprocessor by determining the clock rate. It acts as a metronome, telling the processor how fast to run. According to Wikipedia, the clock rate is "the frequency at which a CPU is running." Processors typically operate at a frequency of about 1-3 GHz (1-3 billion cycles per second) (in Wikipedia, retrieved on Oct. 10 2012, from http://en.wikipedia.org/wiki/Clock_rate).


Memory

  • Samsung
  • Two modules, each 512 MB
103ag memory.jpg
  • On this particular machine, the RAM modules were located directly next to the power supply and the hard disk.
  • According to the article How RAM Works, "a memory chip is an integrated circuit containing millions of transistors (on/off switches) and capacitors (which hold the bit of information--a 1 or 0). In the most common form of computer memory, a transistor and a capacitor are paired to create a memory cell, which represents a single bit of data. The transistor acts as a switch that lets the control circuitry on the memory chip read the capacitor or change its state." Random access memory (RAM) is considered to be "random access" because any memory cell can be quickly accessed directly, in any order, rather than sequentially as they are in CDs or magnetic tapes. Information stored in RAM is volatile and thus only accessible while the computer is running; all files intended for long-term storage must be written to secondary storage (e.g. hard disk, CD, floppy disk, flash memory). (in How Stuff Works, retrieved on Oct. 10 2012, from http://computer.howstuffworks.com/ram.htm)

Hard Disk

103ag harddisc2.jpg
103ag harddisc1.jpg
  • Western Digital (WD2500JD-75HBC0)
  • 250 GB
  • According to Wikipedia, the hard disk drive is a data storage device that is:
  1. Non-volatile, meaning it "can retain the stored information even when not powered"
  2. Random-access (as opposed to sequential access)
  3. Magnetic
  • The hard disk includes a disc coated with magnetic material that rotates on a spindle, and "magnetic heads arranged on a moving actuator arm read and write data to the surfaces." (in Wikipedia, retrieved on Oct. 10 2012, from http://wikipedia.org/wiki/hard_disk)
  • In this PC the hard disk was found below the optical disc drive.










Power Supply

103ag power.jpg
  • According to Wikipedia, "the desktop computer power supply changes alternating current from a wall socket to low-voltage direct current to operate the processor and peripheral devices. Several direct-current voltages are required, and they must be regulated with some accuracy to provide stable operation of the computer." (in Wikipedia, retrieved on Oct. 10 2012, from http://wikipedia.org/wiki/computer_power_supply)
  • The cables found inside the PC are used to supply power to the various machine components.

CD/DVD

103ag cddvd.jpg
  • According to Wikipedia, an optical disc drive (ODD) is a disk drive that uses laser light or electromagnetic waves within or near the visible light spectrum as part of the process of reading or writing data to or from optical discs." The optical disc drive in this PC is a player and burner that acts as both a CD and DVD drive. (in Wikipedia, retrieved on Oct. 10 2012, from http://wikipedia.org/wiki/optical_disc_drive)
  • In this PC the optical disc drive was located above the hard disk.