CIS 1110A - Computer Operating Systems and Maintenance


Module 1

This lesson presents some background on disassembling and reassembling computers. Objectives important to this lesson:

  1. Basic procedures
  2. Tools for working on computers
  3. Procedures for working safely inside a computer
  4. Troubleshooting approaches
  5. Current assignments

Concepts:

This lesson is about chapter 1 in your text, which discusses some basics and some details about computers that fall into one of two form factors: desktops and laptops. Before we begin, you should understand that any discussion of this topic represents a moment in time. Lectures that I gave ten years ago did not address some of the technologies that are common now. Likewise, today's new tech will eventually become something that resembles an antique. When you are preparing for a certificate that says you know something about hardware, you need to know what the certification test covers. With that in mind, rest assured that our author, Dr. Andrews, does a fine job of staying current in her texts. Just be aware that this is a field that requires constant effort to learn the next thing. Keep learning.

The chapter opens with a section on desktops that includes some basic advice that applies to all tech work.

  • The first tip, documentation, is easy, but most people do not do it. It is easy to write down what you do and to make it a habit to write down all changes to system. It is very unusual to find anyone who does it. Ideally, you should take photos or video of everything you see and everything you do. You may not believe me, but you will when you realize you have forgotten how something you took apart was put together when you opened it.
  • The second tip is to remove jewelry that could get caught on anything. I once talked with an engineer (who used to teach at Baker), who told me a story about a colleague who lost a finger due to his wearing a ring that ran afoul of the equipment they were using. The same advice applies to loose clothing, long hair, and your fingers themselves.
  • Organize the screws and parts that you remove from a device. You will need to put them back in the right places.
  • Don't stack circuit boards, motherboards, or expansion cards. Dr. Andrews says that you could dislodge a chip. You could also break solder points, contact points, or the boards themselves. They are not very sturdy.
  • Don't touch anything that conducts signals or electricity. Hold circuit card, chips, and other electrical devices by their non-conductive edges. This protects you and the components.
  • Speaking of touching things, lots of edges are sharp, whether they are metal edges or not.
  • For all tools you use on a computer: do not use magnetic tools. These can cause damage to computer equipment and media.
  • Do not work on the inside of a computer that is turned on, connected to power, or being charged, for obvious reasons.
  • Do not work on power supplies or monitors until you have had specific training to do so.

Example toolkitThe text presents a list of equipment you may need in several situations. This term, our labs are virtual, so you should not need to buy tools, but you should still know something about them. The most needed equipment can vary with the technology you are working on. Take a look at some of the kits discussed in this review. Most of the kits discussed are heavy on screwdrivers and bits. Only a few have wire cutters, wire strippers, and crimpers. Some of them are attractively priced, and others are ridiculous. Common tools you may want to have:

  • Ground bracelet and/or ground mat - a good idea, but not used much in the real world.
  • Phillips-head screwdriver - several sizes here are a good idea
  • Flathead screwdrivers - a wide blade and a narrow blade are useful.
  • Torx screwdrivers - these come in several sizes, and none can be substituted for each other. A good set of them is desirable.
  • Socket drivers for hex nuts and hex screws
  • Flashlight
  • A knife or scissors (you can have both if you add a Swiss Army knife)
  • Extractor, a spring-loaded device that looks a bit like a hypodermic syringe. Press the plunger and wire prongs come out the other end, that can be used to pick up fallen objects. Sometimes you need this, sometimes you need the tweezers. Sometimes you need the much longer version that is available in automotive stores.
  • Tweezers - for picking pieces of paper out of printers or dropped screws from tight places. Surgical forceps are also good.
  • Quick ties
  • Plastic bags
  • Bootable rescue OS on a memory stick

Ports of a computerThe text continues with a discussion of opening the case of a desktop computer. As you may come to expect from Dr. Andrews, she begins by talking about steps to take before opening the case. She points out that you should disconnect all the cables that may be connected to the computer already. On pages 6 and 7, she illustrates several kinds of ports (connection sockets) commonly found on computers. Some of the pictures are not very clear, so take a look at this image, and go to this nice site that discusses several of them.

The image is a bit dated, but it is accurate, and it displays port types that you might never seen on a computer.

Moving on to the next tip, if you are going to open a functioning computer to upgrade it, you should make a backup of its data if there is a chance of losing it. idea, Making backups, is harder to do, and it is done even less often than documentation. Note that the author recommends making backup copies of your data. It is assumed that you have backup copies of your programs and operating system: they are on your original installation/recovery disks. If your system did not come with such disks, determine whether you can create them from a utility on your hard drive. You will need them when your hard drive eventually dies.

Assuming you have made a decision about backup, let's continue with step 2 on page. Many of the steps that follow are obvious, but perhaps the use of the ESD strap is not. Its purpose is to prevent a electrostatic discharge between you and the computer. Note that is does not protect you from a discharge from the power supply. It protects the computer from a mild discharge that you may not even feel. Here is some good advice:

Static electricity - ESD, or Electrostatic Discharge, can be a serious cause of problems. Some numbers from a previous text may help you understand the situation:

  • A human can't feel a static discharge until it is 3,000 volts or more.
  • Normal motion, like moving a chair or a foot can generate 1,000 volts.
  • Simply walking across a carpeted area can generate 1,500 to 35,000 volts.
  • Handling a plastic envelope can generate 600 to 7,000 volts.
  • Picking up a plastic bag can generate 1,200 to 20,000 volts.

Damage can be done to computer parts with 20 to 30 volts. The damage may not cause immediate failure.

Rules of Static Prevention

  • Ground yourself when working on computers. Use a wrist strap, EXCEPT when working on monitors or power supplies. Test your grounds. Unplug computers, as some modern models pass current through the system when plugged in, even if they are turned off. (This tech I know tried to change sound cards while the new Dell was plugged in...)
  • Do not touch electrical leads.
  • Do not touch ungrounded people while working on components.
  • Use static-shielding bags (gray or silver) not antistatic bags (pink or blue).
  • Keep nonconductors, like styrofoam, away from components. They can store static.
  • Don't place components on metal surfaces.
  • Increase humidity to minimize static.
  • Put the computer on the desk, not the floor. Dry room, winter, feet scuffing on a carpet next to a computer: formula for disaster. It's called a "desktop" for a reason.

Review the discussion about opening a "standard" case. The truth is that there are many designs, many that use screws, many that don't, and many that require you to find an owner's manual. The text continues with an introduction to motherboards and expansion (add-on) cards/boards. Look over that if it is unfamiliar to you.

If you are not confused yet, turn to the section of the text on connectors associated with power supplies. This section should sell you on the idea that when you build a computer, you have to make sure that your power supply, your motherboard, and your expansion cards all are compatible with each other. The text tells us that the current A+ tests expect you to know about each of the connectors in table 1-2. This link will take you to a site that displays several of the connectors and several of their matching sockets. That site has a lot of ads, but it also has tutorials on many of the subjects in our text.

If you are not happy reading or linking, you can get a lot of information from the video displayed below. (No, children, there is no such thing as a 'below video'. You have been misled.)


If that one doesn't do it for you, here is another one by Linus, who has lots of videos on YouTube. He has a different style, and he points out different tech facts:


Halfway through the chapter, the author switches to laptop computers. Laptops are typically harder to work on, and harder to reassemble once you get them apart. They usually have batteries that don't last long enough to watch a movie, and they may have very few ports, which are always on the most inconvenient side of their cases. (I have been working on a laptop for my day job for the last six months.) They are meant to be lighter than desktops, usable in any setting (while their batteries last), and portable between work locations.

To overcome the deficiencies that laptops usually have, the text mentions docking stations and port replicators. They are two different things. A docking station typically provides more ports, the ability to use power supply to use or charge the computer, and the ability to connect to a desktop monitor (usually much larger than the one attached to the laptop). As the text points out, a docking station has to be designed to fit a docking port, which is usually on the back or the underside of the laptop. This means you cannot use just any docking station with just any laptop. Port replicators are different. When I am at work, my laptop connect to a port replicator that connects to a USB-C connector on the laptop. This provides power, carries the video signal to a larger monitor, and allows me to connect other peripherals to my laptop. In this case, the line between the docking station and the port replicator is blurred, but that is intentional on the part of the manufacturer.

Like desktops, the next laptop you see may come apart in a way you have never seen before. The author suggests consulting a user manual for advice before beginning to take one apart. She also points out that you may need a service manual for the device, if there is such a manual, for details on fastenings and components. She also suggests that you will have to add more tools to your kit, such as a Phillips 1 bit and a Torx 5. In the video below, the presenter uses a Phillip 8, and a metal spudger.


The text also mentions all-in-one computers, which often resemble a computer built into a monitor. The text tells us there is an A+ objective for this subject, so read through this short section.

At the end of the chapter, there is a long list of advice about maintaining laptops. We will address this in a discussion board next week.

 

Assignments

  1. Read the chapter, and the next one for next week.
  2. Complete the assignments and class discussion made in this module, which are due by 6pm next week.