The Computer and Its Makeup
No matter how these devices are installed onto your computer, whether internally or via USB,
they need a driver to communicate with the operating system.
The power supply has a fan on the backside. Although the PSU fan doesn't play as critical role as it used to,
this fan helps to provide the airflow required to cool the components that reside within the computer and helps to ensure that the computer retains its overall system temperature
The motherboard's main job is
to hold the computer's microprocessor chip and let everything else connect to it. Everything that runs the computer or enhances its performance is either part of the motherboard or plugs into it via a slot or port.
The hard drive is where the operating system that runs the device and its applications is located.
where the operating system that runs the device and its applications is located.
In order to provide power to the computer, the PSU must convert an alternating current, AC
which is obtained from the wall socket, into direct current, or DC, which is used by the computer components.
Optical drives connect to the motherboard
either by an IDE or SATA connector
Turning on a computer isn't as simple as just hitting the power switch. There is a lot that goes on during the boot process. The boot process is the series of steps that a computer takes to start the computer system and open up the operating system.
1. The power button activates the power supply in the PC, sending power to the motherboard and other components. 2. The computer then performs a power-on self-test (POST). The POST is a small computer program within the BIOS that checks for hardware failures. A single beep after the POST signals that everything's okay. Other beep sequences signal a hardware failure. The meaning of the beep sequence depends on the manufacturer of the motherboard. 3. The computer may display information on the attached monitor, showing details about the boot process. This information may include the BIOS manufacturer and revision, processor specs, the amount of RAM installed, and the drives detected. 4. The BIOS attempts to access the first sector of the drive designated as the boot disk. The boot disk is typically the same hard disk or solid-state drive that contains your operating system. You can change the boot disk by configuring the BIOS or interrupting the boot process with a key sequence (often indicated on the boot screens). 5. The BIOS confirms there's a bootstrap loader, or boot loader, in that first sector of the boot disk, and it loads that boot loader into memory (RAM). The boot loader is a small program designed to find and launch the PC's operating system. 6. Once the boot loader is in memory, the BIOS hands over its work to the boot loader, which in turn begins loading the operating system into memory. 7. When the boot loader finishes its task, it turns control of the PC over to the operating system. Then, the operating system is ready for user interaction.
You want to make sure that your computer has plenty of RAM. It is hard to have too much memory. When you purchase a computer, the memory is usually listed in the following format:
8GB (2GBx4) DDR3-SDRAM-1333
DDR memory transfers the data in 64-bit pieces. In order to accommodate this type of RAM, the operating system that manages your computer must support 64-bit processing.
A DDR SDRAM comes as a module that clips into a slot on the motherboard. A pair of clips hold the RAM module in place. You must open these clips to insert and remove the memory. DIMM modules are not compatible.
Once installed onto the computer, the computer and the USB-connected device can communicate with each other. This connection may transfer data between two devices, such as images from a camera to a computer
A USB connection can also be used to power a device, such as charging a smartphone. It can also be used to allow an application on the computer to control the device, such as installing firmware updates on a USB device.
A driver designed for Windows XP may not work for Windows 8, so sometimes drivers are operating-system specific so a driver designed for Windows 8 won't necessarily work for Windows XP.
A driver for a 32-bit operating system will work for a 64-bit operating system and vice versa.
There are thousands upon thousands of devices out there on the market that integrate with computers.
An operating system manufacturer can't possibly keep track of all of the devices out there on the market, so operating system manufacturers such as Microsoft depend on the device manufacturers to create drivers that will install into their operating system and integrate the device with it.
The processor generates a tremendous amount of heat. You should never directly touch a CPU until it has had time to cool down.
All modern-day CPUs today have a heat sink.
Central Processing Unit (CPU)
Also known as the microprocessor; the brains of the computer.
Most computers made in the last 5 to 10 years support IDE.
Although not as fast as SATA drives, IDE is cheaper, which is why it is found on a lot of home computers.
You would then insert two more 4GB memory modules, giving you a total of 16GB of memory. If all of your memory slots are filled, you will then have to replace your DIMMs with larger ones, for instance replacing all of your 2GB DIMMs with 4GB DIMMs, which would double your memory.
Although purchasing a faster processor will speed up your computer as well, doubling your memory will have a greater impact on performance than a processor upgrade.
External devices are grouped into two categories, input devices and output devices
An input device is a device that sends data and commands to the computer. Input devices allow the user to integrate with the computer
Although we have focused on the traditional PC desktop throughout this lesson, the concepts are pretty much the same for laptops as well. Many of the components inside a laptop are physically integrated into the laptop so it is mostly one piece of equipment.
As far as tablets go, most of the components, with the exception of memory, cannot be upgraded, and it isn't cost-efficient to repair a tablet. Your best bet is to trade it in for a new one.
The BIOS is an important part of your computer. It holds the configuration for a number of important settings such as the boot order of your computer.
By default, the computer attempts to boot from the C drive unless it is an old computer that has a floppy drive, which would then be the default. Suppose you want to install a new operating system on your computer from a DVD drive. You would open up the BIOS and configure the boot order so that the computer attempts to boot from the DVD drive first.
When you open up a traditional workstation, you might not see the CPU because it is buried beneath a
CPU fan and/or heat sink and resides in its dedicated CPU slot on the motherboard. Both of these devices help to cool the CPU.
In order to access the BIOS, you must press a designated key right after the POST check. The BIOS usually tells the user what key or keys to press on the upper right-hand corner of the monitor screen.
Depending on the computer manufacturer, this key will be one of the function keys F1 or F2, the ESC key or the DEL key. When you change settings, and attempt to exit, the BIOS will prompt you to confirm if you want to save the setting changes. If so, the computer will reboot.
During this process you must be conscious of electrostatic discharge, otherwise known as ESD.
ESD can damage or destroy the computer or selected components
Much like the shock you receives when rubbing your feet on the carpet and touching something metal, ESD can occur when working in your computer and will cause components you touch to no longer work properly.
ESD can occur without the user's feeling a shock and will only occur while working on the inside of the computer
This all sounds great, but there are some huge drawbacks.
For one, SCSI drives require jumper settings, and very complex knowledge of SCSI systems is necessary to get more than one or two drives going. They're also extremely expensive, often more than two or three times the price of a SATA drive. They charge a heavy premium for their increased performance, and thus are mostly utilized for servers and other business-critical applications. Very few desktop computers are built with SCSI disks in mind.
It is not uncommon for a server today, which is a robust computer that shares resources for multiple users, to have a quad-core processor.
Having a dual-core CPU will allow you to run multiple pieces of software simultaneously without losing the performance and speed that you would when running the same pieces of software on a single-core CPU.
IDE ribbon connectors do take a lot of room within the case, however, which diminishes the air circulation inside.
IDE ribbon cables are gray and have two rows of 20 pins that connect to both the motherboard and to the drive itself.
When you press a key on your keyboard, the CPU receives the input and will interpret the key stroke, sending a command to the monitor through your video card to display it.
If you click the mouse on an icon to open a piece of software, the CPU interprets that command and opens the application.
The paging file is a designated area assigned to the hard drive that spills over from the RAM and is managed by the computer operating system.
If your computer doesn't have enough memory, it juggles data back and forth between the paging file and RAM, as needed.
If RAM is temporary storage in which your computer stores data currently being manipulated, then what happens if your computer is working with more data than the computer has memory?
In this case, the computer has a spillover area called the paging file.
The two primary CPU families today are
Intel and AMD
A good computer doesn't have just a single processor.
It most likely has a dual-core processor that contains two cores on the same processor, essentially giving the computer two central processing units and twice the processing power.
It is literally the brain of the computer
It performs millions of individual calculations every second at phenomenal speeds. A CPU runs programs by fetching instructions from the computer's memory, evaluating them, and executing them in sequence
While workstations use standard size 3.5-inch drives (3.5 inches is the diameter of the storage platters), the drives for laptops come in either 2.5 inches or 1.8 inches, with 2.5 inches being the most popular.
Laptops only have a small area of space beneath their case so space is greatly limited
Your mouse, printer, digital camera, scanner, and other devices probably all connect to your computer via a USB port.
Many memory storage devices, such as portable hard drives and flash drives, are also commonly connected through USB ports.
You should look for driver updates from time to time for all of your devices. Companies release updated drivers to fix bugs and errors found in previous versions
Most device manufacturers provide a way to download drivers for their supported devices. If you need to locate drivers for an old device, third-party driver websites are available that sell drivers for outdated devices.
A hard drive stores nonvolatile memory.
Nonvolatile memory is memory that can retain information even after the power is turned off.
To install an internal device that needs to be connected to the motherboard requires that you turn the computer off. If you do not turn the computer off before inserting a device into a connector on the motherboard, the motherboard will short and you will have to replace it.
Once you remove the cover of your computer case, you are ready to install the internal device into its designated slot on the motherboard.
Hard drives come with two interfaces.
One is an older technology called IDE/EIDE, which stands for Integrated Drive Electronics and Enhanced Integrated Drive Electronics. The other is SATA, which stands for Serial Advanced Technology Attachment.
DDR SDRAM is computer memory and serves as temporary storage for data. Memory such as DDR3 is used by the computer for the temporary storage of data.
RAM is far faster than nonvolatile memory so it is an ideal place for the computer to store data that the computer is working on.
SATAs have only a thin wire as a connector so they take up far less room, which is critical for a laptop or notebook computer.
SATAs also have a much faster transfer rate of between 33 MBs and 133 MBs (megabits per second).
SCSI is most commonly used for hard disk drives and tape drives
SCSI drives are theoretically much faster than either ATA or SATA drives and tend to be much more reliable and much quicker to boot and load programs.
The motherboard has a number of critical components:
Socket Chipset Basic Input/Output System (BIOS) chip real-time clock chip
Fortunately, it is very easy to avoid ESD while working on your computer. Most important, make sure you and the computer are at zero potential by continuously touching the unpainted metal surface of the chassis (the computer power supply case).
Some basic steps to take are the following: • Remain standing at all times when working on the computer. Sitting on a chair can generate more electrostatic. • Always keep a part of your body such as a hand or arm in contact with a metal part of the computer. • Unplug all cords. Make sure everything is removed from the back of the computer (power cord, mouse, keyboard, etc.). • Wear the proper clothes. Make sure not to wear any clothing that conducts a lot of electrical charge, such as a wool sweater.
If you want to make your computer faster, the best thing you can do is add more memory, especially when you consider how inexpensive RAM is today.
Sometimes this may involve purchasing additional DIMMs to insert into empty DIMM slots in your computer. For instance, you may have two 4GB memory modules and two more empty slots.
A large amount of heat is generated within the computer, and without the aid of cooling devices such as the PSU fan, the computer would overheat quickly, which would cause irreparable damage.
Specially designed cases with vents are available that allow better airflow through the system in which the power supply fan can either blow out the air from the back or draw in cooler air, depending on the design of the system.
. When you install a device, in a way you are literally installing the driver of that device.
Take a printer, for instance. Let's say you are installing a new HP inkjet printer onto a Windows 8 computer. If it is a popular printer, Windows 8 may have the driver already.
The CPU can receive instructions from the software at extremely fast speeds and then perform the tasks that are required to run the software.
The CPU will instruct the rest of the hardware components inside your computer to do exactly what the software was written to do.
Small computer system interface (SCSI) is a set of standards for physically connecting and transferring data between computers and peripheral devices
The SCSI standards define commands, protocols, and electrical, optical, and logical interfaces.
If not, Windows 8 will either do a web search for the driver or prompt the user to provide the driver by specifying a location.
The driver may be provided on an installation disk provided by HP with the printer, or it may be downloaded by the user into a folder on the computer.
Installing USB devices is very simple. Simply connect the USB device into one of the USB ports on the computer and the operating system will automatically detect the device.
The first time you connect a new mouse, keyboard, printer, or camera, the operating system will install the designated driver.
This means that the computer has a total of 8GB of memory that is made up of 4 DIMM modules and each DIMM is 2GB.
The memory used is DDR3 SDRAM that has a speed of 1333 MHz. Memory is often placed in pairs. You usually have to insert DIMMs with the same amount of allocated memory in each slot.
When you install a device for your computer, you are actually installing it with the operating system of the computer
The operating system needs to be able to communicate with these devices.
Power supply unit (PSU)
The power supply provides the electrical power for all of the essential components, such as the CPU, hard drives, motherboard, memory, and optical drives.
The "3" stands for third generation, and each generation is twice as fast as the previous generation.
The previous version was single data rate, or SDRAM. DDR SDRAM was built on the technology of the prior version, but operates at almost twice the bandwidth or processing speed.
The socket for the microprocessor
The socket type determines what type of CPU the computer will utilize.
An optical drive is a secondary storage device that offers removable storage. It is called removable storage because you can take the data with you and swap it out.
The three optical drives available today are CD, DVD, and BD or Blu-Ray. Each of these three optical disk technologies has different storage abilities.
The PSU must supply the amount of power that your computer needs to run properly.
There are many charts and calculators out there to determine the power your PSU must generate by inventorying the components of your computer and determining their cumulative power-consumption demands.
The form factor affects where individual components go and the shape of the computer's case.
There are several specific form factors that most PC motherboards use so that they can all fit in standard cases.
USB cables will usually have two types of connectors, one on each end.
There is a USB type A that is the end that always plugs into your computer. The other end has a different type of connector depending on what type of device is being connected. Printers and some cameras take Type B, while phones and other types of handheld devices take Mini or Micro connectors.
The term EIDE also refers to an ATA standard known as ATA-2 or Fast ATA.
Therefore, the terms EIDE, ATA-2, and Fast ATA may be used interchangeably.
The majority of the connectors are 4-pin connectors.
These are called Molex connectors, and they connect to various hard drives and optical drives. If your computer has a SATA drive then it will require a SATA adapter.
USB ports are the most common way to connect peripheral devices to a computer.
These ports allow the user to insert USB standalone electronic devices into them.
In fact, these spindles spin at a rate of 5400 RPM, or rotations per minute.
This creates a lot of heat and contributes to the noise level of the computer.
Occasionally you may need to install an internal device such as extra memory DIMMs or an internal network interface card (NIC).
This is a more complicated process than installing a USB device.
This slows the computer down a lot because accessing data from a hard drive is much slower than accessing it from RAM.
This is also referred to as drive thrashing, as the hard drive is constantly spinning for the paging file, which then affects the performance of the drive as well. Every time your hard drive is running an LED light near it will flicker indicating activity. A good sign that your computer doesn't have enough memory is if this light is constantly flickering.
Volatile memory, in contrast, is memory that loses its data as soon as the power is turned off.
This is characteristic of what is referred to as random access memory, or RAM. RAM is temporary storage. It is the memory that stores the data that is being processed in real time.
Some of the internal devices that the power supply provides power for are connected to the motherboard. Because these devices are plugged or integrated into the motherboard, the power supply needs to plug into the motherboard or the devices themselves.
Thus, the PSU has a series of connectors. One type of connector feeds power to the motherboard.
A motherboard that supports DDR2 will not accept DDR3, and vice versa.
To ensure that a user doesn't insert a DIMM into a motherboard that is incompatible, the DIMM modules have a notch on them that is located in a different place for each module, making them easily identifiable. They also have different pin counts. SDRAM has 168 pins, DDR SDRAM has 184, and DDR2 and DDR3 have 240.
Computers today use a type of RAM called DIMM, which stands for dual in-line memory module
Today's more prevalent type of DIMM is DDR3 SDRAM, which stands for double data rate synchronous dynamic random access memory.
It is better to have a PSU that is too big than too small.
Total power requirements for a personal computer may range from 250 watts to more than 1000 watts for a high-performance computer with multiple graphics cards. Personal computers rarely require more than 300 to 500 watts.
Within a matter of minutes, the device is ready to run.
USB devices are referred to as plug-and-play devices. Plug them into the USB port and they are ready to run.
USB stands for
Universal Serial Bus
EIDE is an improved version of the IDE drive interface and provides faster data transfer rates than the original standard.
Whereas the original IDE drive controllers supported transfer rates of 8.3 Mbps, EIDE can transfer data up to 16.6 Mbps, which is twice as fast.
It is very important to make sure that the air vent for the PSU fan is free of dust and other collected materials that may dampen or hamper the airflow.
You can lightly brush off this exterior area of the PSU or use a can of compressed air to blow it clean
For instance, say you open up Microsoft Word to create a document. The Word application resides on a SATA drive, which is nonvolatile memory. It is always there to be accessed
You then begin to create a new document. The document you are working on resides in RAM. When the document is completed, you save it to your hard drive. If your computer were to lose power before you saved the document, the document would be gone because it was never saved to nonvolatile memory.
Most current ATX motherboards require two power connectors from the power supply:
a primary connector that contains 20 or 24 pins that carries all voltages, and a secondary 12-volt "CPU" connector that includes 4 or 8 pins and supplies power for the processor.
a heat sink with a fan is called an
active heat sink
A traditional hard drive
also called a hard drive disk, or HDD, is actually a collection of small DVD-like disks called platters that spin very fast around a spindle as an arm reads and writes to the disks.
Heat sinks are generally made of
an aluminum alloy and often have fans.
The chipset is part of the motherboard's logic system
and connects the CPU to other parts of the computer
The real-time clock chip maintains
basic settings and the system time. This component requires a battery that needs to be switched out every once in a while
USB devices have to be installed by the operating system
but this process takes place automatically unless the operating system cannot determine what the device is or cannot locate a driver for it.
The North American standard
is the NEMA 5- 15.
A heat sink without a fan is called a
passive heat sink;
Intel is the industry leader, and is considered the go-to manufacturer of higher-end processors
s. AMD is for the more budget-conscious computer owner
Output devices receive or display output
t from the computer.
Most PSUs will have either a 110 V/220 V switch
that you can manually set to choose either voltage or will automatically detect which one is needed
The shape and layout of a motherboard is called
the form factor.
The Basic Input/Output System (BIOS) chip controls
the most basic functions of the computer and performs a self-test every time you turn it on.
• CD: Holds about 700MB of data. CD drives can only play CDs. • DVD: Holds about 4.7GB. DVD drives can also handle CDs. DVD DL, which stands for Dual Layer, holds about 8.5GB.
• BD: Holds about 25GB. The drives are CD- and DVD-compatible. Blu-Ray is so named because it uses a finer, blue-violet laser for reading data.
There are also solid-state drives, or SSDs, which have no platters. SSDs have a number of advantages over HDDs:
• Faster I/O rate, or in/out rate; in other words, how fast the drive can read or write data. • They use a lot less energy and run quieter because nothing is spinning. • SSDs have no moving parts so there are fewer things to go wrong. • SSDs are not affected by fragmentation
The following are common types of input devices:
• Keyboard • Mouse • Digital scanner • Digital camera • Stylus or pen • Webcam
Some common types of output devices include
• Printers • Monitors • Flat panels • Projectors • Plotters • Speakers
A few more acronyms are often used in discussing optical drives:
• ROM: This stands for read-only memory and indicates a disc that cannot be written to, only read. • R: This is a disc that can be written to once. This is applicable to all formats, but there's a bifurcation that will be discussed later on. • RW: This disc can be written to, erased, and written to again. This is again applicable to all formats. • RE: Only applies to Blu-Ray and is the equivalent of RW.
Other things that you can do within the BIOS include but are not limited to the following:
• Set or change a BIOS password. This is a password separate from the operating system. The BIOS will not allow the computer to move forward through the boot process without it. • Change the CPU settings. A common setting to change is to turn on virtualization if the computer will host virtual machines. • View the memory configuration of the computer.
