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So far in this course, troubleshooting your PC has meant lots of time in front of your monitor, changing software settings and configuring networks. But what if your video card stops working? What if your hard drive goes “click, click, click!” and then dies? What do you do? When it comes to troubleshooting PC hardware, you need to get your hands a little dirty.
You won’t actually get dirty, of course, unless you don’t keep your PC clean. You will, however, finally get your hands on the components that actually power your PC. Where does the hard drive go? Where does the RAM (random access memory) connect to the motherboard? You’ve probably seen pictures, but looking inside your own case can make it that much more real.
Before we get ahead of ourselves, you need to understand the power of each component. This knowledge comes in handy any time you need to replace an old part. I’ll show you where you can improve performance and how to shop for the best parts.
When working inside the PC case, you also need to think about safety. I’ll walk you through some tools and tips that will protect you (and your PC) from any unfortunate errors.
Finally, we’ll go inside your PC and check out where everything goes. This will come in handy for Lesson 10, when we’ll discuss how to replace components.
When you’re ready, proceed to Chapter 2 for some more information on hardware and improving your PC’s performance.
When buying a new PC or parts for upgrading an existing one, you need to understand how each part affects its performance. Every component that makes up your PC plays an important role, but each role works differently.
Many factors determine how quickly a computer can obey you. You can't judge performance by a single factor, because so many devices come into play with a seemingly simple request. When you double-click a program icon, such as Solitaire, the central processing unit (CPU) responds because it understands—through the operating system—what you want it to do. The CPU sends a message to the hard drive: "Hey! Retrieve the files for Solitaire and send them to RAM so I can work!" Once the RAM has the files, the CPU can obey your demand and process those files. Then it sends commands to the video card processor to put Solitaire on your monitor.
Most computer performance benchmarks revolve around three factors: speed, capacity, and sophistication.
Speed: CPU, RAM, and video card processor speed is measured in hertz, which translates into the number of times per second each component can do things. If you had a processor that ran at one hertz, it could process one line of code each second. Modern components run much, much faster than that, into the millions and billions of cycles—the technical term for "doing things"—per second.
A 1-gigahertz CPU can churn through one billion calculations per second. That's pretty fast, but 1 GHz pales in comparison to today's processors! Typical CPUs now run in the 2.5+ GHz range.
Because the CPU handles the vast majority of the work in processing, increasing CPU speed offers your biggest bang for the buck in terms of increasing the overall speed of the computer. That's not the only thing you can do to increase performance speed, though. Faster system RAM and faster hard drives can have a major effect. A higher-quality video card—with a faster processor and faster RAM—can likewise prove invaluable for enhancing performance, although you'll typically see the performance gains only in graphics-intensive games.
Hard Drive Capacity: Hard drive and RAM capacity can have a major impact on computer performance. Not enough of either one can destabilize a computer or cause you to be unable to run some programs. How much do you need? To make capacity numbers make sense, we've got to get down to the basics.
You need a hard drive big enough to store your programs and your data, plus some left over for the operating system to use. If you run low on space (below 10% of the total capacity of the drive), your computer slows down. Only your particular needs can determine how much hard drive space you should have. My primary work system, for example, has Windows 7 and a slew of productive and not-so-productive applications (including Office, Photoshop, Illustrator, iTunes, Half-Life 2, and World of Warcraft).
Windows and my necessary work applications take up several gigabytes. Just one of the games I play (Half-Life 2) takes up over 5 GB of hard drive space! My primary hard drive needs to be big enough to hold all that and still have room to store data and add new programs. For instance, Windows 7 officially requires 16 GB of available space. Add that to your list of applications, and you quickly run out of space. Fortunately, modern hard drives cost very little (compared to earlier models) and offer acres of data storage.
Memory Capacity: The CPU uses system memory to hold the programs and data that you're currently using, including the operating system. This means the amount of RAM you have directly affects performance. If you don't have enough to run your OS, load your applications, and have space for data files, your system can crash or prevent you from accomplishing your computing tasks.
You can never have too much RAM. More RAM means that you can have more programs and processes running at the same time. Having more RAM on the system also means that the CPU has to make fewer trips to the hard drive for data.
What's an adequate amount of RAM to have? It depends on what you use your computer to do. In general, you need at least 2 GB to run Windows 7 efficiently. Windows 7 can run on less, but everything that you do will take longer. Starting with that base number, you should increase RAM depending on your machine usage.
Because I tend to have a lot of applications open all at the same time—email, Web browser, Word, Photoshop, and Illustrator—my system needs a lot of RAM. With just those programs mentioned plus Windows, for example, my PC uses over 1 GB of RAM. When I'm putting together images for this course, the data files (photographs and illustrations) can add at least another 200-300 megabytes!
Tip
Software makers list the minimum and recommended hardware requirements for their programs on the packaging of their products or on their company website. These estimates are usually more theoretical than practical. Double those numbers for a more realistic idea of how much RAM you'll need to run a program efficiently.
Sophistication: The sophistication of devices can have a profound impact on a computer's performance. CPUs sold today, for example, go from low-end processors that run productivity applications just fine but stumble on anything demanding to ones that can run the latest and greatest game or video production software with ease. Video cards vary wildly in performance and features, and if you choose incorrectly, you're in for a bad computing experience.
CPU manufacturers offer new and improved processors almost as quickly as the Gap changes clothes offerings. Video card manufacturers are even worse (because there are more of them playing the game). To be an informed computer user means going to the Internet to look up the latest offerings. One of the most accessible sources for current information is Ars Technica.
You might want to buy the most powerful model you can find, but think before you spend. After all, you don't need a top-of-the-line system if you only intend to play solitaire! If you only want to use the Internet, any modern computer can handle it right out of the box. Period. On the other hand, if you expect to play the latest 3-D games, mix music CDs, and edit digital video, then skip the entry-level, budget PC and go for something better.
Don't swipe that credit card yet! After you square away your hardware and software, you still need to consider what happens after you drive off the lot.
Don't leave the store (or complete the online transaction) without finding out about the manufacturer's warranty—what the company will do if the product has defects—and the store return policy. If you're buying from one of the larger retailers, you can also count on them trying to sell you an extended warranty or service plan.
A new computer usually comes with the manufacturer's warranty, which ranges from one to three years. Factory-refurbished machines (new computers that were returned to the store and sent back to the factory for repair) generally come with much shorter warranties—around 90 days. Most warranties cover repair or replacement of hardware components that fail because of a manufacturing defect, but not accidents or mistreatment. In other words, they'll probably replace your monitor if the tube burns out from normal use, but not if you drop it or if you use the "whack it on the side" method to try to get a clearer picture.
Extended service agreements offer tech support beyond the duration of your original service agreement. Your computer maker or a third-party company may offer these plans.
Make sure that you're clear on the details of your retailer's return policy before finalizing your purchase. Most computer stores have a very limited return policy on computers, and may charge a restocking fee at the time of return—meaning they charge you for the hassle of having to return your money and deal with now-used equipment. Don't simply take your salesperson's word about what's covered—get it in writing.
Once you have your shiny new hardware, you'll probably want to install it right away. First, however, you need to read Chapter 3 and learn about safety for you and your PC.
People love playing with technology. New computers have that new smell and shiny paint job. Even new components can add freshness to an older PC. It would really ruin your day, then, to get that new part home and have it not work because you inadvertently broke it.
Handle PC components carefully. They may not appear fragile to physical impacts, but other things can damage or destroy them without you realizing what's happened.
At the same time, your PC can hurt you, too. Lots of heat and electricity pass through your computer, so watch out when you go inside the case. This chapter discusses all the safety issues you should be aware of when you work with your PC.
If you decide to open a PC while reading this chapter, as I encourage you to do, you must take proper steps to avoid the greatest killer of PCs: electrostatic discharge. ESD simply means the passage of a static electrical charge from one thing to another.
Have you ever rubbed a balloon against your shirt, making the balloon stick to you? That's a classic example of static electricity. When that static discharges, you may not notice it—although on a cool, dry day, I've been shocked so hard by touching a doorknob that I could see a big, blue spark!
I've never heard of a human being getting anything worse than a nasty shock from ESD, but I can't say the same thing about computers. ESD will destroy the sensitive parts of your PC, so you need to take precautions.
Note
All PCs are well protected against ESD on the outside. Unless you take a screwdriver and actually open up your PC, you don't need to concern yourself with ESD.
ESD takes place only when two objects that store different amounts (the hip electrical term to use is potential) of static electricity come in contact. To avoid ESD, you must keep yourself and the parts of the PC you touch at the same electrical potential. You can accomplish this by connecting yourself to the PC via a handy little device called an antistatic wrist strap. It consists of a wire that connects on one end to an alligator clip and on the other end to a small metal plate that secures to your wrist with an elastic strap. You snap the alligator clip onto any handy metal part of the PC and place the wrist strap on either wrist.
Static electricity, and therefore the risk of ESD, is much more prevalent in dry, cool environments.
Antistatic wrist straps are standard equipment for anyone working on a PC, but other tools might also come in handy.
The moment you take an internal PC component out of the PC, it no longer has contact with the systems and may pick up static from other sources. Techs use antistatic mats to eliminate this risk. These mats act as a point of common potential; it's very common to buy a combination antistatic wrist strap and mat that all connect to keep you, the PC, and any loose components at the same electrical potential.
Antistatic wrist straps and mats use tiny resistors—devices that stop or resist the flow of electricity—to prevent an antistatic charge from racing through the device. These resistors can fail over time, so you should read the documentation that comes with your antistatic tools to see how to test them.
Any electrical component not in a PC needs to be stored in an antistatic bag, a specially designed bag that sheds whatever static electricity you have when you touch it, thus preventing any damage to components stored within. Almost all PC components come in an antistatic bag when purchased. Experienced techs never throw these bags away, as you never know when you'll want to pull out a part and place it on a shelf for a while.
Always put components in an antistatic bag, not on the bag.
Although having an antistatic wrist strap with you at all times would be ideal, you might find yourself in a situation where you lack the proper antistatic tools. This shouldn't keep you from working on the PC—if you're careful!
Before working on a PC in such a situation, touch the power supply every once in a while as you work to keep yourself at the same electrical potential as the PC. It doesn't work as well as a wrist strap, but it can keep you safe if you need to get inside your PC.
One final question on ESD—should you work with the PC plugged in or unplugged? The answer is simple: Do you really want to be physically connected to a PC that is plugged into an electrical outlet? The chances of electrocution are slim, but why take the risk? Always unplug a PC when working inside it.
When a magnetic field interferes with electronics, we call this electromagnetic interference. EMI poses a much smaller threat than ESD, but it can damage components and erase data on some storage devices. You can prevent EMI by keeping magnets away from computer equipment.
Certain components are particularly susceptible to EMI. Never get a magnet close to:
Unfortunately, we often use things with magnets in them without even knowing it. Any device with an electrical motor has a magnet. Many telephones have magnets. Power bricks for laptops and speakers also have magnets. Keep them away!
Do you ever hear strange noises on your speakers even though you aren't playing any sounds? Do you ever get strange noises on your cell phone? If so, you've probably run into radio frequency interference (RFI).
Many devices emit radio waves:
In general, the radio waves that these devices emit are very weak, and almost all electronic devices use shielding to prevent RFI. A few devices—speakers in particular—remain susceptible to RFI. It doesn't cause any damage, but most people find it irritating. To prevent RFI, keep radio-emitting devices as far away as possible from other electronics.
Computer gear manufacturers package their product in a variety of ways to shield against accidental damage, whether that's physical damage, ESD, EMI, or RFI. The typical pink translucent computer bag has a filmy coating that prevents the bag from producing static electricity and helps protect the contents against physical contact (and thus damage).
Caution!
The bags provide proper protection only when sealed, so when you're storing a component, fold over the open end of the bag and slap a piece of tape on it.
IT techs live in a dangerous world. We can trip, hurt our backs, and get burned by hot components. Let's take a moment to discuss these safety issues and what to do about them.
The basic tech toolkit consists of a Phillips-head screwdriver and not much else—seriously—but a half-dozen tools can round out a fully functional toolkit. Most kits have a star-headed Torx wrench, a nut driver or two, a pair of plastic tweezers, a little grabber tool (the technical term is parts retriever), and a hemostat to go along with Phillips-head and flat-head screwdrivers. A nut driver helps you tighten nuts and bolts. A hemostat is a clamp that looks like a pair of scissors.
A lot of techs throw in an extension magnet to grab hard-to-reach bits that drop into cases. Many also add a magnifying glass and a flashlight for those hard-to-read numbers and text on the printed circuit boards (PCBs) that make up a large percentage of devices inside the system unit. Contrary to what you might think, techs rarely need a hammer.
Now that you know how to work with your computer safely, let's carefully open it up and look inside. Check out Chapter 4 when you're ready.
If you've never opened a computer before, you might feel nervous about all the horrible things that might happen. Don't worry. Your computer won't bite you. In fact, opening up your computer can teach you a lot about how it all works.
Nothing beats seeing your own components power your PC. You can identify most of the major components without even removing them from the case or motherboard. This chapter leads you through an exploration of the inside of your PC case.
This exercise might remind you of the biology labs in which students dissect animal specimens—but unlike in those biology labs, your specimen has a good chance of leading a perfectly normal life afterward!
Before we begin, you'll want to have the following tools ready:
Shut off the power to your system and unplug the power cord from your PC and from the wall socket before proceeding.
Disconnect all the external cables (monitor, keyboard, mouse, printer, and so on) from the PC you're going to use. Place it on a flat, stable surface (preferably on an antistatic mat) near which you can sit or stand comfortably to inspect the insides.
Use proper antistatic procedures while opening the case and during this entire exercise. Using whichever method applies to your case (thumbscrews, Phillips-head screws, locking tabs, or Torx screws), remove the cover of your system unit. (There's more about this step in the FAQs.) Then lay the system down so that the open side faces the ceiling.
Don't try to open up your laptop (or your smartphone or tablet). You'll just end up with 100 little pieces and a broken laptop. Manufacturers don't design mobile devices with replacement parts in mind; if a part on a laptop fails, you'll need to ship the laptop back to the manufacturer for repairs.
Look inside your system case. What do you see? To begin with, you'll see lots of cables and wires. Most colored wires originate at the power supply and end at the various devices to supply the needed direct current (DC) power to run the PC. The wide ribbon cables attach at various points; your computer uses them to transfer data. Techs sometimes refer to these as logic cables or data cables.
Look inside the PC and find the expansion slots. How many total expansion cards is it possible to plug into your system?
Some of the expansion slots may have cards in them, including modem cards, sound cards, network cards, or video cards. Since expansion cards expand the capability of the computer system, you install them after you assemble (or the manufacturer assembles) the system unit.
Look at the expansion cards installed in your PC, and then look at the external connectors on each. Can you match the cable to the expansion card?
Locate the power supply, a large silver or black box in one corner of the system unit case. Trace the colored wires leading out of it. Remember to be gentle!
Look for the hard drive and optical drive in your system. (There may be more than one of each.) These rectangular silver boxes are usually in brackets at the front of the case. Each drive should have two cables coming out of it: one for data and one for power.
Current systems use small, seven-wire data cables for serial ATA (SATA) hard drives and optical drives; these cables have connectors shaped like the letter L. Older systems use wider, 40- or 80-wire flat ribbon cables. Both of these wider cable types have a colored edge on one side for orientation.
After noting the current state of the cables, disconnect and reconnect each device's cable in turn. Practice this a few times. Can you plug a cable in backwards? Try it. Plug the cable into the device the wrong way if you can. (Don't force it.)
You can plug in older types of cables incorrectly, but newer cables and connectors have built-in keying (connector fitting) to prevent this from happening. Make sure to properly connect the cables when you've finished.
Look in your PC, and find the random access memory modules. RAM comes in thin, wafer-like modules, about three to five inches long by one inch wide. A row of metal contacts running along one of the long edges plugs into a matching socket, three to five inches in length, located on the motherboard. Look for a long wafer standing on its edge; often you'll find two or more RAM modules lined up in a row. How many RAM modules do you have?
Look in your PC, and see if you can locate the central processing unit. Running CPUs generate a fair amount of heat, so they need their own dedicated cooling mechanisms. Because of this, when you search the motherboard to find the CPU, you'll generally find it hidden under a fan or a heat sink unit. (A heat sink is a device that transfers heat from a solid object—like a CPU or a graphics processor—into the air or a liquid.)
Now check out the motherboard. If you didn't realize it already, you've been staring at it this whole time. The motherboard is the central printed circuit board in your computer; everything inside the PC case connects to it. Some motherboards include lots of ports and expansion slots, while others have only a few. Does your motherboard fill the entire case?
When you finish your exploration, make sure you've left everything as you found it and close the case.
If you've never looked inside your own PC before, you might feel a little overwhelmed. Don't worry. Next time won't feel so nerve-wracking. This chapter only introduced you to the inside of your PC case. Pretty soon, you'll be replacing parts like a champ.
Before you check out the quiz and assignment that go with this lesson, please visit Chapter 5 for a review of everything you learned.
This lesson introduced you to the hardware powering your PC. You already knew about how computers work, but now you know more about each component and have (hopefully) seen them with your own eyes. You’ve just begun your journey inside your PC, but you’ve already learned some important things about PC hardware troubleshooting.
We discussed PC performance in terms of speed, capacity, and sophistication, and we connected each to one or more components in your PC.
You also learned what to look for when shopping for components, such as buying guides and warranties.
You learned how to keep you and your PC safe. Electrostatic discharge (ESD) can quietly ruin a perfectly good PC part. Make sure to ground yourself with an antistatic wrist strap or mat. Also, be sure to store any unused components in an antistatic bag to keep them safe. Other things to watch out for include electromagnetic interference (EMI) and radio frequency interference (RFI).
Watch out for tripping hazards like cables and power cords, which might hurt you or your PC. Don’t lift heavy boxes with your back—use your knees. And don’t touch anything near a fan or heat sink. Those devices imply that something nearby can burn you.
You explored the inside of your PC. Don’t be afraid to open up your computer and check out the internal hardware. Inside your case, you can see your power supply, motherboard, expansion slots and cards, drives, RAM, and more. Remember where all these things go!
In the next lesson, you’ll go inside your PC again . . . only this time, you’ll learn how to replace some internal PC components.
Before you start Lesson 10, check out the quiz and other supplementary materials for this lesson. And if you have questions about opening up your PC, please come talk with me in the Discussion Area.
Ars Technica, a popular technology news site, frequently compiles a list of the best hardware options across a range of budgets. You’ll find parts and prices for budget boxes costing $750 all the way up to the “God Box,” which costs over $13,000! Of course, you can always mix and match different ideas from different setups, but this guide provides a great starting place for building your own PC.
A: People often ask this, but it’s difficult to answer because each manufacturer makes its cases differently. Before you try opening it, however, make sure you’ve turned it off and unplugged it from the wall.
Start by looking for screws or latches along the outer edge of the rear side of the case. I’ve seen anywhere from one to eight screws securing a cover to the case. (Some don’t use any screws.)
Once you’ve removed the screws or released any latches, most cases pop off if you pull backward on the case, away from the front of the tower. Sometimes, only a single side disconnects. Other cases connect all sides of the case in a single piece of metal that gets pulled off.
Reattaching the cover mostly involves reversing the removal process. You’ll probably need to line up some edges to make sure it slides on properly, but once you do, you only need to reattach the screws (or whatever device keeps the cover in place) to close it again.
A: While most people probably buy their computer equipment new, many local computer stores and online retailers also sell used components and computers. Used parts cost less, but you might only find older stuff. The part will also have some wear and tear, so it might not last as long as a fresh part. When purchasing from a store (local or online), be sure to check out the return policy. Don’t trust used parts to be reliable just because the person at the store says so. You need an escape plan!
You could also buy computer equipment from a friend or other individual. This, however, carries with it a secret price. If you buy something from a friend and it breaks, you will get mad at that friend—trust me. If your relationship can’t handle that kind of stress, don’t do it.
Go online and find some new parts for your PC. Because you've just begun your PC hardware journey, you don't need to find anything too specific. Using Ars Technica's System Guides, or other sites like newegg.com or amazon.com, find the following list of parts:
You can probably find hundreds of models for each. How much do they cost? Could you still buy all three on a budget of $200? What do you lose in performance by doing so?
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