Hardware Skills. Page 1 of 12

Transcription

1 Hardware Skills First, identify the parts on the front of an assembled computer... Monitor Keyboard Mouse CPU Floppy Drive, CDROM Drive Power, Reset Buttons Identify what you have What type and speed of Processor? How much RAM? How big hard drive? Special boards or interfaces? Are there network, bios, or other settings we should record? Next, identify all the input/output ports on the back... Page 1 of 12

2 Compare connectors, features, older vs. newer, male vs female... Keyboard (AT, PS/2, USB) Mouse (Serial, PS/2, USB) Modem (RJ11 telephone jack) Serial USB Parallel (DB25) SCSI Firewire Sound In/Out Video In/Out Monitor (VGA) Game Paddle Other? Clean the Mouse Clean the Outside of your Computer (Does not apply to optical mice!) There is nothing more frustrating than a flakey mouse Think of it as an upside-down trackball. Remove the ball from inside -- use 2 hands and twist. It can be washed with plain, soapy water. Rinse and dry thoroughly. Do not reinstall it until it is completely dry. Use canned air to remove dust from the socket Internal contacts can be cleaned with Q-TIP/swap and alcohol. Use very small amount, do not wet insides. Canned air and vacuum. Damp cloth with plain water and a small amount of mild soap. Do NOT GET ANY ELECTRONIC PARTS WET! Use a Q-TIP with Isopropyl Alcohol to remove sticky or stubborn dirt -- be careful not to spill alcohol on electronics! Page 2 of 12

3 WARNING: PLEASE FOLLOW INSTRUCTIONS CAREFULLY Carefully Disassemble a Known-Working Computer Instructions BEFORE Opening the CPU Cover First backup any user work. Ideally, perform a FULL BACKUP of the hard disk (or verify that it has been done recently, for certain). Do a PROPER Shutdown! (Start -> Shutdown... ) Turn off ALL Peripheral Devices (e.g., external modem, disk) Remove ALL Cables! Work in a Dry Area with Shoes/Sneakers On! NEVER Open a CRT (Monitor). CRTs contain large capacitors which store charge. They store enough charge to cause serious injury even 2 WEEKS after being unplugged. Also, if a CRT gets smashed, the implosion results in glass flying in every direction. If you determine that a CRT is defective or needs calibration, refer it to a qualified service technician. Page 3 of 12

4 Avoid Static Electricity Damage to Computer Parts: Use Anti-Static Wrist Strap to Handle All Electronic Components Must be grounded to chassis or grounded work-area Hold Boards by EDGES Only Do Not Use Magnetic Screwdrivers Handle ICs with Extreme Care, Only by Ends Set Parts Down on Grounded, Anti-Static Surface, or in Static-free bags, with component-side UP If you are an expert--supervised by a trained adult--it is sometimes acceptable to plug in power to the chassis, as a method of grounding. You might see me doing this. NEVER DO THIS WITHOUT PERMISSION AND EXPERT SUPERVISION. Always use extreme care around the power supply and power cables. Usually, if you avoid scraping your feet on carpeting before working on the computer, the metal chassis will provide sufficient grounding anyway. Be extra cautious working on All-in-One computers (such as emachines or beige Power Macs). It is OK to open the CPU area to gain access to the motherboard, add RAM, and so on. It is NOT OK to reach inside or up into the CRT area. Refer to the instructions above regarding CRT dangers. Do not open up a laptop computer, until you have had substantial additional training. It can be very tricky to get all the cables back in place, and it is very easy to damage the LCD display. ADVANCED ACTIVITY: Ask one of the instructors to help you CAREFULLY remove the keyboard or bottom cover(s) from a laptop computer, such as to add RAM, upgrade the hard drive, or (e.g., ibook models) install a wireless card. For any cable, connector, or screw, which might get confused or which can be attached in more than one way, take careful notes. Use a baggie or similar to hold small parts. Be Sure You Remember How to Put Everything Back Together! Keep small, similar parts in a tray or baggie Check if there is more than one way that a connector could fit If so, be sure to note the color/order of each connection. Don t be shy about labeling cables, including up/down/left/right Page 4 of 12

5 Do NOT take things apart beyond the point where you know you can recover! Do not take apart the disk drive -- they are hermetically sealed, and once opened are no longer of value. Identify the Internal Components Power Supply -- the biggest and easiest to find -- where does the power cord plug in? Notice that the power supply almost always includes a FAN. Notice the THINK power cables versus the THIN (e.g., ribbon) variety for data cables. Most devices require both. Motherboard or Main Board or System Board Advanced: Manufacturer and Model (find specs on Internet) Slots Advanced: Bus Type (e.g., (E)ISA, PCI) Integrated Circuits (ICs) Floppy Drive (3.5 versus 5.25 ) Hard Drive(s) CDROM Drive(s) DVD? CD-RW? Other Removable Storage (e.g., Zip Drive, Tape Drive) Heat Sink and Muffin Fan for Microprocessor Page 5 of 12

6 Micro-Processor (Manufacturer, Model, Speed) Random Access Memory (RAM) slots How many are full? Can you figure out the density of each? Cache Memory? Video RAM? Read Only Memory (ROM) Video Board (or Video Section of Motherboard) Modem (Internal or External) Network Interface Card (NIC or Ethernet Card) Battery (NB: these come in several sizes and shapes) Page 6 of 12

7 Explain the Purpose of Each Component and How they Work Together Some Key Concepts of Computer Science Every Component Requires a Source of Power and a Data Path Processing data requires energy. Computer Data is Stored as On/Off Patterns. Everything (numbers, letters, words, pictures, can be represented as numbers in the BINARY NUMBER SYSTEM. Bits and Bytes Count from 0 up to 7 in binary Explain the relationship between OCTAL, HEXADECIMAL, and BINARY representations of data. Learn the ASCII Character Code A = 65. = a = 97. = Which bit gets turned on when you hold down the Shift key? Take apart a 3.5 floppy disk. What s inside? Take apart a 5.25 floppy disk. What s inside? Which holds more? What is a Kilobyte? Megabyte? Gigabyte? Terabyte? NB: 1K = 2 10 = Moore's Law: A factor of two (in size, cost, speed,... ) every 2 years. (It s really more like every 18 months?) Processor Generations and Processor Speed (Megahertz) Intel 286, 386, 486, Pentium I, II, III, IV Motorola 68020, 68030, 68040, PowerPC, G3, G4 Sparc, Ultrasparc,... NB: Processor Clock Speed Does Not Always Predict Performance Page 7 of 12

8 Carefully Clean the Insides of your Computer Dust and Dirt are Enemies of Computers! The Read/Write Heads float on a cushion of air which is smaller than a large dust particle. Muffin Fans and Electric Current combine to attract dust and dirt into the computer. A clogged fan can block air circulation and "melt down" the cpu. Take Pride in your work: Always clean a computer when you service it A clean computer is more likely to be a reliable computer Use Canned Air Use Mini-Vacuum Cleaner Be Very Gentle! Do not actually touch the components. Do not Use Liquids Adding and Removing Components Remove a RAM SIMM/DIMM ( Memory Stick ) Wear Anti-Static Wrist Strap, properly grounded. Each end of memory stick has a clip which holds it in place-- bend outward. Notice the orientation so that you can put it back correctly. Tilt to 45 degree angle and slide it out Use thumb and forefinger of each hand. Never force it! If it doesn t come out easily, something is wrong Doing this improperly can damage the motherboard and ruin the computer permanently Page 8 of 12

9 Add a RAM SIMM/DIMM ( Memory Stick ) You should have already checked how much RAM is currently detected by the OS. Wear grounded antistatic wrist strap. Identify the correct slot(s). Know whether SIMMs/DIMMs must be installed in specific locations, or in matched banks or in matched pairs. Know whether any dip switch settings are required (probably yes on older computers; probably no on newer computers. Sometimes you have to remove smaller (lower density) modules to make room for newer (higher density) modules Tilt to 45 degree angle and gently insert, holding by ends Push downward and toward upright angle -- gently Never force it! Verify how much RAM is now detected by the OS If you get serious hardware errors (inability to start up), the stick is probably just not seated correctly. Remove, re-seat, retry. Remove a NIC/Ethernet Card Be Sure to Wear Anti-Static Wrist Strap, properly grounded Removing any retaining screws Holding the board only by the edges, gently pull it upward, away from the slot. Do Not Force it! Add a NIC/Ethernet Card Be sure you have the right card for the Computer Model -- is it a PCI slot or an (E)ISA slot? Remove the cover plate Install gently -- Do Not Force it! Add retaining screw (if appropriate for Computer Model) Later, Install and Configure Software Driver. Replace the Clock Battery Page 9 of 12

10 Remove the Hard Drive Be Sure to Wear Anti-Static Wrist Strap, properly grounded Removing any retaining screws Hold the drive only by the edges. Sometimes there is a mounting bracket that you need to reuse. Do not force it. Install a Larger Hard Drive Be sure you have the right type of drive for the computer model: ATA SCSI Configure using jumpers or dip switches, depending on the make and model. ATA drive would normally be set to primary master if it will be the C: drive of the computer. SCSI drives require termination and a unique ID number, normally from 1 through 6. Later, ensure that BIOS detects drive information correctly, then format and partition. Page 10 of 12

11 Laptops Laptops require additional caution. The parts are smaller and more delicate. Once removed, it can feel much like putting the toothpaste back into the tube. Each brand and model can have unique ways of connecting peripherals or adding accessories. Here are some pictures from one example, illustrating the PCMCIA (or PC ) slot, the second battery slot (which can hold a CDROM drive or floppy drive) and so on. Plastic inserts/spacers protect the PC slot when there are not cards in use. Use care when inserting cards, do not force. Page 11 of 12

12 Page 12 of 12