Computer Hardware Maintenance

March 18, 2013 under Computer Hardware Maintenance

Computer Hardware MaintenanceLet us go back to some true computer hardware basics: computer hardware maintenance. Computers are volatile creatures. One moment they’re running fine, the next they may just crash. Granted, more often than not this is a glitch in software that is running. However, it may also be caused by a physical problem. Maybe a component is a bit out of place. Or it can even be that a film of dust is causing a part to overheat making the system unstable. Whatever it is, it is always good to take preventative action in order to save your system from any damage that can be caused if something is left unchecked.

Hardware failure’s most common cause is directly related to physical damage. Dropping a laptop, kicking over a tower that is on the floor, being too harsh with internal components are probably most of the incidents that cause damage. Therefore, there are some things you will want to do to limit the number of digital casualties due to our imperfections.

Do you carry a laptop around often? If you do not have a laptop case, then you may be walking around with a dead one very soon. Out of any computers, laptops probably suffer the most abuse, not counting mobile phones ;) . While they are made to take some unintentional abuse, they really cannot take much without loosening or damaging internals. Therefore, if you must drop it, then drop it when it is in a case. Also, if you have dropped it in the past, when you are using it, you may want keep it as flat as possible, especially for magnetic hard disk drives so that the head does not scratch a platter. They are usually very close together, so any jolt can cause damage and make the platter spin unevenly.

Keep your computer free of dust as much as possible. Fans pull in air to circulate around and cool internal components. The air is then pushed out of the system by another fan. Well, our houses are filled with tiny dust particles constantly floating through the air, especially if you have carpeting, clothes, bedspreads, or other things in the room where your computer is.

As the fan pulls in air to cool everything down, it pulls these little contaminants in where they may find a home and settle down on some hardware. As the months pass, more and more of these particles get caught in the computer and form a layer of dust over the hardware. This causes heat from the computer’s running parts to be retained, thus increasing the temperature of the components and possibly damaging them. Dusting the inside of your computer every month or two(or as needed) will help prevent this.

Electric dusters and compressed air do the job well. Dust all of the components on the inside and the fan vents as well. You may want to use an electric duster over compressed air because it is better for the environment and will save you money in the long run.

You should be cautious when handling computer components. You will need to be grounded when touching components to avoid any electrical transfers from you to the machine. It is best to wear an anti-static wrist strap and attach it to a metal part on the computer case.

Also, if you work on computers a lot, it is good to have an anti-static mat to put under the unit or any component you are working with.  This is especially important if you are working in an area where static electricity is easy to come by, like on a carpet.

Remember, before working on a computer, always unplug it from its power source. Then press and hold the “on” button for a few seconds to discharge any stored electricity. Never work on a computer when it is plugged in. Do not work on a power supply, either, unless you are trained to.

It has been said in the past to keep your computer running all of the time. Not only is that extremely wasteful, from an environmental standpoint, but in the long run, it will reduce the life of your computer. Just like your own body or even an automobile, rest is needed. A constant strain on any physical thing is not good for it. It will fail at some point. Even though starting your computer with a cold boot is taxing, unless you start it multiple times a day, there really should not be anything to worry about.

Turning it off, or at least putting it in a hibernation mode after you are done with it each day is good. Throughout the day, sleep modes are very useful for conserving energy and keeping your computer in a ready state for when you need to use it quickly.

Finally, if you remove internal components, it is a good practice to place them inside anti-static bags. This may be going a little overboard for some, it is always best to err on the side of caution, especially if you are working on someone else’s computer.

Physical maintenance of computer components is vital for a computer to stay healthy for a long time. Just remember to always be safe when working on computers. Also, do not take chances when handling internal components as they are very sensitive. Many of the items mentioned in this post are not necessary, especially if your computer is in a clean environment and handled with care. However, they are useful if you are in a dusty environment or you work on other peoples’ computers since you may not know how they treat them. So never slack on computer hardware maintenance.

Computer Hardware Suppliers

Computer Hardware

Before heading into building a computer or just working with the hardware, obviously you need to get it supplies from somewhere. So here is a list of some of the major computer hardware suppliers today.

Tiger Direct -icon A personal favorite. In business for over 20 years(according to the site), Tiger Direct iconhas a huge variety of pc components as well as ready-to-use systems. They also sell bare-bones kits, which are a good start for a someone just beginning understanding how to build a computer. They easily have some of the best prices around on hardware and basically everything else they sell. Much of the time they have free shipping(not all of the time) and in certain states you may not even have to pay sales tax, thus you get an extremely good deal. They also have good customer service and fast delivery times. They even include explanations of parts on their website. On a side-note, CompUSA is now part of Tiger Direct.

Newegg – Another excellent retailer in the same vein as Tiger Direct. One of best online tech retails, hands down.  Their prices are in line with Tiger Direct, so they are very competitive. They have a vast variety of parts and whole systems; basically anything you can think of.  And just like Tiger Direct, they sell more than just computer supplies. Both of these great stores seem to have the same values that are the basis of their business model; they are very customer service oriented.

Amazon -  What doesn’t Amazon sell? Amazon is the go-to internet retailer of choice, and the reasons are obvious. They have very competitive prices and fast. They are well-known and trusted, something very important for an internet company. They also have great return policies if you are not satisfied with what your purchase. While they are not necessarily tech-focused, they still offer a vast product line and great prices; another recommended retailer.

Bestbuy – Few people have not heard of BestBuy. It’s an old-fashioned brick and mortar biz that’s been around for years. While it is a competitive business and has an online presence, it tends to be more expensive than online retailers, such as Tiger Direct and Newegg.

So if you are buying a computer or building a computer, then these are some of the best computer hardware suppliers around. The two favorites are Tiger Direct and Newegg by far; they offer a huge variety of products, customer service is good, shipping is usually fast, and the prices are seriously hard to beat. These are recommended. While Amazon is recommended as an online retailer in general.

However, whichever online company you choose to do business with, ALWAYS do research on them before your first purchase. Check forums and the BBB for other customers’experiences. This could save you much pain and frustration later on if you find out that the company you used is fraudulent. The internet is still FULL of shady websites and that is not likely to change anytime soon. Other than that, continue on with learning computer hardware basics, and if you can, practice with the hardware itself. Experience is always the best teacher.

Bytes and Hertz

bits, bytes

You will not be able to get a full understanding of computer hardware basics without knowing how their capabilities are actually measured. Knowing how to tell how a piece of hardware performs when comparing it to others is very useful when buying your own or helping someone find a good deal. Thus, let us review some of the main terms used to describe the speed and capacity of pc hardware.

Byte Me and…

You many not really understand what they are all about(or you do and that’s why you’re interested in this site in the first place), but you have probably seen them before. Bits, the 1’s and 0’s running across the computer screens on movies or TV shows when a virus supposedly attacks a computer or something. Believe it or not, all of the logic behind computers revolves around these little 1’s and 0’s. These bits are the smallest unit of memory or informational storage in any computer and either have a value of 1 or 0.  1 means that the section of memory holding the bit is set to “yes” or “true”, while 0 means  that it is “no” or “false.”  A bit is “true” when an electric current passes through it; it is then on.

Bits are used when describing how much information it transferred by a piece of hardware at a single time.  You usually hear of CPU’s and how they process 32 to 64 bits at a given time nowadays. However, you usually find memory stated as kilobytes(210), megabytes(220) , gigabytes(230), and terabytes(240).  So, for example, one kilobyte is 1,024 bytes and one megabyte is 1,048,576 bytes. Many people erroneously say that a kilobyte is 1,000 bytes or a megabyte is 1,000,000 bytes.  Remember, bytes measured as powers of 2, a binary system. This is different from the decimal system we use for counting, which uses powers of 10.


Computer disk drives: Storage capacity for magnetic drives is usually between 250 gigabytes and 4 terabytes. You will not really see anything under 250 gigabytes anymore. Hard disk drives’ capacities are higher , in general, than solid-state drives’, which are available in up to 2 terabyte capacities .  Data transfer rate is also different. The current hard disk drives can transfer data at up to around 140MB(megabytes) per second. Current solid-state drives can transfer data up to around 600MB per second.

…It Hertz

The Hertz measures how many cyclical actions are completed in a second , a frequency of how much something happens. CPU’s today are usually between 1 Gigahertz(phones, netbooks, tablets) and 6 gigahertz(high-end computers). Of course the higher the rate, or clock speed, the faster the hardware processes data. In one cycle, the processor does everything needed in order to receive data and transmit commands. CPU’s and memory modules, etc, need to have a speed rating compatible with the motherboard. They must be able to operate at the speed of the motherboard.


As previously indicated, computer processors are usually between 1Gigaherz and 6Gigahertz. The standard clock speed for DDR 3 RAM at present is between 100Megahertz and 266Megahertz. Video cards have clock speeds from around 166Megahertz to 5700Megahertz

The preceding was a general explanation of bytes and hertz. A lot more can be discussed when talking about these topics. Further your research, because they are important things to know and necessary when developing an understanding of computer hardware basics.

comments: Closed tags: , , ,

Computer Hard Drive

January 18, 2013 under Computer Components

A critical component of any computer today is the hard drive. The hard drive is hardware that stores data on your computer so that programs can be run and use your system’s hardware resources. Your files such as photos, videos, and music are stored on the hard drive. Computer hard drives have come a long way since their beginning. Compared to then, they can hold massive amounts of data, they are much smaller, and they are much less expensive. Really, throughout their history, their cost has continued to decrease while their storage capacity increases. This is definitely good for the consumer.

We will discuss several general topics about hard drives that will be good to know when learning computer hardware basics. These will include the main types on the market today, physical characteristics, and some of the inner workings of them.

Hard drives can be either internal or external. The most common for years now have been magnetic, SATA and PATA drives. These are very fragile, mechanical drives that are the standard in computers. Recently, however, a newer technology has started making an impact on the HDD (hard disk drive) market, Solid-State drives. We will discuss main points about both.

Magnetic Hard Drives

There are three main parts to SATA/PATA hard drives. First, the hard disk is made of platters, or disks, that store data. The second main component is the host adapter, usually found on the motherboard, which allows the computer to understand the data being transferred from the hard drive. Finally, you have the controller chip. As its name suggest, it controls the functions of the hard drive. It controls the motors that spin the discs and receives signals sent by the drive. On a semi-side note, PATA stands for Parallel Advanced Technology Attachment and uses a 40-pin connector for parallel data transfers. SATA, Serial Advanced Technology Attachment, uses a newer 7-pin connector for serial data transfer.

The inside of hard disk drives are extremely sensitive to small debris and will crash or malfunction if contaminated. Therefore, they are sealed before being sold. The circular platters need to be totally dirt and dust free for the read/write heads to extract and transfer data. The read/write head is located on a mechanical arm that moves it across one side of a platter, allowing it to find specific data addresses on the disc. This platter is closely situated near other platters to form the shape of a cylinder. One head is associated to one specific side of a platter. So if there are 3 platters in the hard drive, there will be a total of six heads. Each disc platter is divided into tracks that spiral around their surface. These tracks, in turn, are divided into sectors that can hold 512 bytes of data. The controller understands the layout of the disc and receives instructions from the BIOS when reading and writing data to and from the platters. On the other hand, the BIOS must receive information from the controller to understand the layout of the drive.

File systems are put on the tracks to group certain amounts of memory into clusters so that the hard drives can receive unique addresses for data to be stored and found. This being the case, two or more files cannot occupy one single sector. This means that once a file is using a sector, if there is still more memory in that sector that is not being used, it can never be used, due to address limitations. This inefficiency will result in data waste. This works the same way for clusters created by the file system. But since clusters are larger than sectors, even more data is wasted.

Internal Hard Drive & External Hard Drive:


Whereas the conventional disk drives discussed above are susceptible to physical damage due to their moving parts and fragility within the relationship between the heads and platters, solid-state drives have no moving parts at all. Think of a flash drive (or thumb drive/jump drive) when thinking about a SSD. These newer devices use integrated circuits to store data and are considerably faster than older magnetic disks when reading and writing data. There are several downsides to Solid-State drives at present. First, they are considerably more expensive than magnetic disk drives with less memory storage. Also, as data is accessed, it shortens the useful life of the drive itself. However, as development becomes more efficient, the pricing will decrease, and the capabilities will increase.


Those are the main computer hard drives available today. Future posts will go more in-depth about the characteristics of each. In your quest for learning computer hardware basics, continue to research on your own these components. Hard drives are complex, just as computers are. One post could not hope to cover all you can know about them.

Solid-State Hard Drive:

Source 1:
Quentin Docter, et al. CompTIA A+ Complete Study Guide. 2009

Source 2:

Source 3:
My brain

PC Repair Tools

July 5, 2012 under building a computer
pc repair tools So computers are complex machines. Really, they are some of the most advanced machines in the world. You may be wondering, "Since these are so complex, how could I ever work on one or put one together? Wouldn't I need a professional for this?" Well, the answer is no … and yes. Unless you have studied computer hardware and have the machinery to work on the more fragile and intricate

areas of a PC, there is not much you can do with one. For example, if your power supply fails, do not automatically take it a part and attempt to repair it. In fact, do not do anything with it at all. Leave it to a computer technician to fix.

On the other hand, maybe you want to install a new hard drive or swap out some RAM. These are tasks that you may be able to perform yourself if you choose to do so and follow the proper computer safety rules. However, in order to perform a job correctly and efficiently, you need to use the correct tools. You will need to find a good computer toolkit, with the correct PC repair tools to do the job. Let us discuss this a bit.

Good computer toolkits include multiple kinds of tools designed to work with maintaining computers, of course. Though, unless you are a professional, you do not need thousand dollar tools when working on your system. Here is a list of some tools you should have in your kit:

Screw drivers – Wow, simple, right? But just think about how much metal is being joined and held together by screws inside your PC's case. They are all over your computer. And unfortunately, they are not all the same size or kind. So one screw driver will not be enough, unless it is a special one. Certain screw drivers are made that allow you to swap tips. This prevents you from needing 50 different screw drivers in your toolkit. It is very convenient.

Anti-static wrist straps – This may not necessarily be a tool used to actually work on a computer. However, you should not be working on a computer without one, plain and simple. This protects you, as well as your computer's components from accidental electrical transfer. So, it is for your safety as well as your computer's.

Wrenches – Another standard tool used with computers as well. Smaller wrenches can be useful, such as wrenches ranging from about 4mm to 10mm.

Anti-static mats - You most likely will not find one of these in a computer toolkit, however, they are still valuable. Just like the anti-static wrist strap protects from unwanted electrical transfer, so does this. Whenever you are working on a computer, you should put it on an anti-static mat.

Soft brush – This is not much of a tool either, but when working with computer hardware, you might as well clean off the dust that has settled on it. This is important too, as this dust can cause components to over-heat and ultimately fail.

So there you have a starter list of PC repair tools that would prove useful in any computer technician's computer toolkit. They do not seem to be complex tools for working on a computer, but you definitely should have these. Be sure that whatever toolkit you choose, the tools should be de-magnetized to avoid possible corruption of data when they are in close proximity to hard drives. The deeper you get into learning computer hardware basics, you will come across other tools, such as soldering irons, electronic testers, and other tools. For now, these are all you need to take apart or build a computer. If you are ready to start working on your computer, check out places like Tiger Direct or Amazon. They have a wide variety of toolkits at various price points.

comments: Closed tags: ,

What Is a Motherboard? – Part One

June 6, 2012 under Computer Components

So you are ready to start buying your computer hardware to build your first computer. That is great. Your journey to learn computer hardware basics starts with the board that births all other circuit boards, or something similar to that. If you have no motherboard, you have no computer. The type you choose directly dictates the other hardware you will be getting for your computer. So what is a motherboard, and what are some of its characteristics? The following information will explain what a motherboard(or system board or mainboard) is and the major parts it has, in general. Due to this topic's complexity, it will be divided into multiple posts.

The motherboard physically connects all other components, thus allowing a computer to run as a whole. It is usually located either at the side or the bottom of a computer case. Of course, how a system board fits in a case is very important. That is why you will want to make sure what case you are getting conforms to the size of your board.

System board form factors are classified as ATX, BTX, or NLX(the major ones used today). ATX boards are most popular today. They are designed to run cooler and allow full-length expansion cards to be installed. Micro ATX boards can work with normal-sized ATX and smaller ATX cases. They are similar in design to their bigger sibling, just smaller. Of course, with less surface space, they have less space for memory, expansion cards, integrated components, etc. Also, they are designed to require less energy, using smaller power supplies. So, adding USB peripherals(which use energy from the computer if they do not have there own power adapter), can eventually stress out the power supply. NLX boards are mainly used for more horizontal computer cases. Expansion cards are placed on sideways expansion slots. Therefore, expansion cards sit parallel to the motherboard. Finally, BTX motherboards were released a few years ago. They allow for better cooling using passive heat sinks. This also allows for a quieter system, as less fans are needed.

So what are the major parts of a motherboard? Here is a list below with a quick description of each.

  • Chipset - Circuits integrated to the motherboard using a Northbridge and Southbridge(data paths) to allow the CPU to communicate between the system board and other components.
  • Expansion slots – These are ports where you install components to the mainboard, like video cards, network cards, RAM, etc. These use buses to communicate with the CPU.
  • Power connectors – These feed power into internal components from the power supply.
  • Disk Drive Connectors – These connect the hard drive and other disk drives to your the mainboard
  • Keyboard connector – These connects a keyboard to your computer.
  • Peripheral ports – These connect peripherals, such as a game controller or microphone.
  • BIOS – This is firmware(a type of software) used to run a test(POST) to make sure components are working. It then starts the boot processor of your computer until your operating system takes over. It has an interface where you can change important settings for your computers components, among other things.
  • CMOS battery – This allows the BIOS to always have power running to it, even when the computer is off.  This is so CMOS memory can store user settings and specified component parameters for the BIOS.
  • Jumpers, DIP switches – These are used to allow the correct electrical voltage to transfer to the computer hardware on the motherboard.
  • Firmware – This is software that is actually encoded into computer hardware that can be run without instructions from an operating system. The BIOS uses this type of software to run before an operating system, such as Windows, starts.

Describing in detail the components of a motherboard is out of the scope of this post. However, we will start trying to tackle that in part two of "What Makes a Motherboard?" in a future post. In any case, this is a good start to understanding what a system board is and what it is made up of. Continue researching so that you may take your computer hardware basics knowledge to new heights!

Buying Computer Parts – Part 1

May 15, 2012 under building a computer, Uncategorized

If you are building a computer, it would be nice to just be able to buy the parts needed and simply snap them into any motherboard. Unfortunately, it is not that easy. There are several factors you must take into considerations when getting the correct parts. In theis first post of the "Buying Computer Parts" series, we will discuss the performance specifications you will want to think about when choosing what components will make up your computer. These things are very important to consider because they have a direct effect on how your computer will perform running constantly changing software over the next few years – or if it will run at all. All computers age over time. They ecome slower running newer, more demanding applications. However, planning ahead will allow your computer to age more gracefully. So let us get started in our first discussion of computer hardware basics – building a computer from scratch.

The first component that you will want to choose is the most important as all other parts will be chosen based off of their compatibility with this. This is the motherboard. Motherboards have standard sizes, or form factors. They directly affect how many and which compnonent ports are on the motherboard. If you plan on installing many cards, including graphics, RAM, etc. or plan on upgrading your computer in the future, make sure to pick a board that has many ports and that is easy to upgrade. So make sure how many ports there are to install RAM. See if supports dual and tri- channel memory. You will want SATA support for hard drives. If you do not need a graphics card, make sure that the mother board includes its own video hardware. Find out what CPU's the motherboard accepts by checking what ind of slots it has. Also, check USB support; 3.0 is the current standard. Check for other ports you may want as well, such as firewire, etc.

To find the right CPU, make sure it fits in the CPU slot on the motherboard. You will most likely want at least a dual core processor. Intel and AMD both make dual core processors. However, if you want improved performance, they also make multi-core processors with their latest desings, supporting up to six or more cores. Clock speed is also important as it will improve performance. Also, the higher the cache storage(you will see it displayed in specs lists), the faster the processor will be able to send instructions to the rest of the computer.

Picking RAM includes looking for data storage capacity – most sticks store at least two gigabytes. You will also want to make sure if they support dual or tri-channel modes to improve performance. The motherboard must support these features as well for them to work.

Hard drives are easier to pick. SATA drives are the standard, but newer generations transfer data quicker. The most current and fastest revision is 3.0. Of course you will want to make sure how many bytes of data can be stored. The average range is between 500 gigabytes and two terabytes. It all depends on what type of files you will be saving and how many. Solid state drives are the newest thing in hard drives. They offer a noticeable boost in speed. However, they have a smaller capacity and are much more expensive at this time.

For CD/DVD/Bluray drives, you will want to make sure if they read and write and know their write speed. You will also want to know which versions of discs they accept.

When searching for power supplies, you will want to know their wattage. They are usually between 300 and 800 watts. If you want to build a computer for normal use, such as office work and using the internet that do not require much power, you can stay around the 300 watt area. If you are building a computer that requires more power, such as a gaming machine or one that runs demanding business, programming, or design multimedia applications, you may want to try the 500 and above range. Also, remember that the more USB peripherals you connect to your computer that do not have their own power supply, the higher the capacity power supply you will need.

For video cards you will want to see how much RAM is installed. You will also want to take note of what type of RAM is installed as speed differs a lot with video cards. The GPU is also another component that is important. Make sure of its processing speed. Also, know which ports are attached to the card. These include VGA, s-video, DVI, and HDMI For network cards, you should see what kind of networks they support. wifi support? Ethernet? For sound cards, you will want to know its polyphony capabilities and if it supports surround sound, its sampling rate, and output ports.

And there you have your first lesson in computer hardware basics. The information above is not exhaustive. It is just to provide some basic information to get you started in building a computer that is right for you. Of course, you can use this when you are just buying a computer as well. Future posts will consider the attributes and characteristics of these computer components in more depth.

Computer Hardware… What Makes a Computer?

May 5, 2012 under Computer Hardware Basics

Computers are complex machines, some of the more complex in the world. For the most part, however, all brands of computers have the same parts. They may have different cooling systems or versions of parts, but they are all used for the same purpose. Here is a list of parts that make up these amazing machines. Get to know these parts and you will be well on your way of having a good knowledge of computer hardware basics.

Computer Case Central Processing Unit Floppy/CD/DVD/BLU Drive Monitor
Power Supply Graphics Card Fan Network Card
Motherboard Sound Card Data/Power Cables Keyboard
Hard Drive CD/DVD/Bluray Drive Mouse RAM

As you can see from this list, there are a good number of parts, but nowhere near something like a car. the complexity comes in where there are many different brands and versions of these computer components. You cannot just buy a motherboard and some RAM, for example, and expect them to work together. Certain configurations are required for these parts to be able to communicate and work together. Below is a quick list of descriptions for what each part does.:

1 )Case – Protects internal components
2 )Monitor – Output device – allows programs to be visible to the eye.
3 )Mouse – Device that controls user input to the computer.
4 )Keyboard – Another device that controls user input to the computer.
5 )Power Supply - Accepts and converts electricity from an outlet to useable power for the computer.
6 )Motherboard – Frequently referred to as the backbone of the computer. Without it, there could not be a computer.
7 )CPU(Central Processing Unit) – The brain of the computer. Processes data and issues necessary commands.
8 )Hard Drive – Stores saved memory.
9 )RAM(Random Access Memory) – Stores memory needed for software to run.
10 )Graphics Card – Processes specific data to produce visual output on through a monitor.
11 )Sound Card - Processes specific data to produce audio output through speakers.
12 )Network Card – Converts network communication signals between computers
13 )Floppy Disk Drive - Accepts floppy disks that store saved data.
14 )CD/DVD/Bluray Drive – Accepts CDs/DVDs/Blurays for reading and writing data.
15 )Power/Data Cables – Provide power to components and data transfer between components, respectively.
16 )Fan – Cool down computer components with air circulation.

So there you have a simple breakdown of standard computer hardware. Future posts will feature more in depth information on their attributes and uses. Learning computer hardware basics is not a fast process. So for now, try to memorize these components and their simple descriptions.

Learn Computer Hardware

March 1, 2012 under Uncategorized

Would you like to learn computer hardware basics? Are you apprehensive about getting involved with computers? They are, after all, very complex machines. Do not let that get to you, though. As with everything else, learning to work with computers takes the proper mindset. Do not let that get to you, though. As with everything else, learning to work with computers takes the proper mindset. A lot of effort is needed to solidify your knowledge of computer hardware. You will need to memorize, for the most part, and just think logically about what makes a computer work.

Also, if you plan on having a career in computer hardware support your learning will never end. The tech world is constantly changing, so you will need to continually watch for the next generation of computer components and understand their attributes and configurations.

Learning computer hardware basics is not hard. But it will take time and effort on your part. However, whether you have a career in computer hardware, or if it is just a hobby, or you want to just be able to work on your own computer when you need to, the more knowledge you gain, the better. This website is designed to help you to learn computer hardware.