Computer Shopping Techniques

When it comes to wisely shopping for computer equipment, there are some techniques that will increase your chance that your purchase will have the following characteristics:

1. You will get a good price.
2. You will get a good product.
3. You will get what you expected when you order.
4. You will get the order when you expect it.
5. You will not get ripped off.

Shopping Steps

1. Research the product you want to buy. Read the reviews at on-line magazines such as zdnet.com. Also computer gaming websites may review sound cards and video cards. Another technique to find reviews is simply to go to a search engine or a super search engine and search for reviews on the product you are looking into buying. For instance go to mamma.com and search for "asus video card reviews".
2. Be aware of somewhat deceptive pricing. This refers to the fact that various vendors charge a wide variety of amounts for shipping, even when you are buying product of similar weight and cost. This is because some vendors build some of their profit into shipping costs. This should not prevent you from purchasing from a particular vendor, but if you are aware of it, you will know what you are paying. This pricing policy will make the vendor show up with a deceptively lower price on a price search engine.
3. Use price search engines to find the vendors with lowest price.
4. Use web sites that compile customer ratings on vendors to tell what vendors have good reputations.
5. When you place your order:
   1. Be sure your order is placed using a secure server so no one can steal your private information.
   2. Always use your credit card such as Master Card or Visa. This is another line of protection between yourself and the vendor. If you have trouble such as not receiving the product but still being billed for it, they can look into the problem.
   3. Check shipping costs before finishing your order.
   4. Print a copy of your order and get and print your order number.

Computer Hardware Manufacturers

• Microprocessors
  • Intel
  • AMD
• Motherboards
  • Asus
  • AOpen
  • Abit
  • Biostar
  • Gigabyte
  • Micro-Star
• Hard Drives
  • IBM
  • Seagate
  • Western Digital
  • Maxtor
• Video Card
  • 3Dfx
  • Asus
  • ATI
  • Creative Labs
  • Diamond
  • Jaton
  • Matrox
• Sound Card
  • Creative Labs
  • Yamaha
  • Diamond
• Network equipment
  • 3Com
  • D-link
  • Linksys

Computer Hardware Terms

Terms

• bit - A logical data unit which has a possible value of 0 or 1.
• byte - A unit of data storage consisting of 8 bits.
• cycle - An electrical cycle is basically a sinewave form during which electrical voltage will cycle from its lowest negative value to its highest positive value and back again.
• computer hardware - Refers to the various electronic components that are required for you to use a computer along with the hardware components inside the computer case
• hertz - A unit of frequency describing the number of electrical cycles that occur in a second. One hertz is one cycle per second. Power is delivered to homes in the United States at 60Hz and in Europe at 50Hz.
• megabyte(Mb) - A unit of data storage consisting of about one million bytes. This is normally used to refer to the amount of system memory or floppy disk storage.
• megahertz(Mhz) - A unit of frequency. It is one million hertz. It describes the clock frequency the microprocessor runs at. The larger the number, generally the faster the microprocessor, but there are other factors that affect microprocessor speed.
• gigabyte(Gb) - A unit of data storage consisting of about 1000 megabytes. This is normally used to refer to the amount of capacity a hard drive has.
• RAM - Random Access Memory

Keyboard and Mouse

If you would really like to get any use on your computer, you would probably like a keyboard and a mouse.

Keyboard

Keyboards can range in cost from about $10 to $100. I generally stay with less expensive keyboards, but I try to avoid buying a keyboard with the large type PS/2 connector as mentioned in an earlier section. There are keyboards with a different feel or sound when key pressing is done. Some people are particular about the feel and sound. If you are, you may want to spend a little more for your keyboard. You may even want to buy it from a retail store so you can test the feel of it. There are special keyboards with extra functions on them for such things as surfing the internet.

Mouse

The mouse interface of choice is the PS/2 interface rather than the older serial interface. Using a PS/2 interface will not require the use of a serial port on your computer. There are a few types of mice available. The main choices are between:

1. Two or three buttons
2. Center sprocket wheel

The choice of two or three buttons depends on your preference and whether the software you run on your computer will support a three button mouse. If it does not support three buttons, it just means that you will not be able to use the third button. Many mice today have a sprocket wheel in the center which will allow the user to scroll up and down documents on the screen by turning the wheel. Also some mice are "ergonomic". I'm sure I misspelled that word.

Depending on features and the quality of the internal roller ball and mechanisms, a mouse can cost anywhere from $2 to $50. Or possibly you can find one in your back yard or basement for free.

Monitor

Monitors are used to view your data on a computer. The characteristics of your monitor are very important for your system performance since the quality of your video will significantly affect your computing experience.

Components

Most monitors today consist of a picture tube and electronic control circuitry which are used to transfer the signal to the screen. There are some monitors that do not use a picture tube, but use electronics to display information. These monitors are more expensive and are not usually very large, but are primarily used for smaller computers such as notebooks and laptop computers. We will not discuss the flat video displays in this section at this point in time.

The primary and most expensive component in a standard monitor is its picture tube. The most important characteristics of a monitor generally refer to picture tube specifications although other circuitry can also be important in providing picture clarity. A picture tube is basically a large vacuum tube with a phosphorescent coating on the front of it. At the back of the picture tube is a large electron gun ( actually 3 guns ) which shoot(s) electrons onto the phosphorescent coating at the front of the tube. When the electrons strike the coating, the coating glows. The coating provides the primary colors which are green, red, and blue. These component colors and their combinations can be used to make every other possible color combination. There is other circuitry which works with the gun to direct the electron gun to the proper color at the correct time, and to direct the gun to the correct location on the screen depending on the phase of the video signal that is being sent to the monitor. There is magnetic circuitry which is used to bend the electron beam to strike the appropriate area on the screen. This is referred to as deflection.

The yoke is an electromagnetic coil used to guide the beam to its intended location. The color pattern on the phosphorous appears like the three colored circles shown on the left side of the drawing below. There are many of these color patterns on the screen. The closer the groups of these three patterns are, the better the resolution of the monitor can be. Monitor resolutions refers to the number of lines per inch that can be seen on the screen. It is rated in vertical (up and down the screen) and horizontal (left and right) terms.

Important Specifications

Some of the most important specifications on the monitor are:

1. Screen size - Expressed in inches, it is the approximate size of the picture tube when measured from the lower left corner to the upper right corner.
2. Spacing - Expressed in dot pitch. This is the description of how close the three color patterns are spaced apart in the screen. The smaller number, the better.
3. Maximum resolution at a specific frequency. This refers to the amount of pixel resolution viewable on the screen at a specific scan frequency. The higher the pixel resolution at a higher given scan frequency, the better the monitor is. Generally I look for 19 inch monitors that will support 1200X1600 pixel video resolution at 80Hz. Currently a good monitor for the price is the LG Electronics 995E for under $300.00 at pcnation.com.

How dot pitch spacing can be deceiving

Different manufacturers and vendors rate dot pitch different ways. There are actually three characteristics of dot pitch. They are:

1. Horizontal
2. Vertical
3. Diagonal

As you can see depending on how the dot pitch is measured, you may get different numbers. You will need to carefully check manufacturer's specifications to be sure the monitor you buy has the spacing you think it has. I was once interested in purchasing a monitor that according to the article I read had a dot pitch spacing of .22 mm. When I looked at the vendor website for that model, it stated .26 mm. I went to the manufacturer's website and it stated .22mm horizontal and .22mm vertical. So I did the math.

.22 squared +.22 squared = .26 squared

Also read the reviews on the monitors to see which ones have the best performance.

Other storage devices

Other storage devices include: DVD Drive - DVD stands for Digital Video Disk. Most DVD drives use the ATAPI interface. They are available as internal or external devices. They can operate at up to 16X speeds but 8X is more common. They are primarily used for video storage but they can be used to hold audio and computer data. DVD is categorized into DVD-Video and DVD-ROM devices. The DVD-ROM device is for computer data storage. Zip drives - A removable cartridge storage device that may be used to store compressed data as a data back up method. A zip drive has between a 100Mb to 2G storage capacity. Cost is usually between $45 and $350. Some zip drives can also be used to read standard 3.5 inch floppy diskettes. Tape drive backup kits - Their capacity 3G to 40G. The cost range is from $200 to $1000. More about DVD-ROM There are five recordable versions of DVD-ROM. They can all can read DVD-ROM and DVD-Video discs, but different type of disc is used by each one for recording. DVD-R/authoring - Can record data once. DVD-R/general, - Can record data once. The capacity is 3.95 Gb or 4.7 Gb. DVD-RAM - It is not compatible with current drives. It has a storage capacity of 2.58 Gb It can be rewritten about 100,000 times The discs are expected to hold data for 30 years or more. DVD-RW - The capacity is 4.7 Gb. It can be rewritten about 1,000 times. DVD+RW - It will become available in early 2001.

CD-ROM

The storage capacity of most CD-ROMs is about 650Mb of data. Originally CD-ROMS were read only devices, but now read/write technology has been developed.

Interface

Many CD-ROMs are interface to the computer using the ATAPI interface. This is ATA Packet Interface which is a IDE interface. This is designed for extra drives like CD-ROM's and tape drives that connect to an ATA connector. The ATAPI interface is the standard interface for IDE controlled CD-ROMS. If your CD-ROM uses an a ATAPI interface, it should be supported by all available software. If you are using a SCSI controller, you should probably use a SCSI CD-ROM. There are two primary types of CD-ROMs today.

1. Read only
2. Read and Write CD-ROM

These are primarily available as an internally mounted drive, but can also be purchased as an external device. There are some CD-ROM drives that interface through the parallel printer port.

Speed

The primary performance concern of CD-ROM drives is their speed. Speeds are expressed in terms of 1X, 2X, 4X, which is the number of times the drive is than the standard CD-ROM reader. Of the read only type, speeds have exceeded 50X. CD-ROMS of up to 40X speeds and beyond can be purchased today for a reasonably low price.

The read/write type of CD-ROM speeds are expressed with three values. They are read, write, and rewrite. Current speeds of these devices are 32X, 10X, 4X. Currently 32X by 8X by 4X are priced reasonably at around $220. This compares to a 40X read CD-ROM drive at around $30-40. Therefore we recommend you do not rely upon your read/write CD-ROM drive for reading normal CDs especially where playing games in concerned. You could wear out your expensive CD-ROM performing read operations which costs a great deal more than a read only CD-ROM!

Hard Drive(s)

Construction

Hard drives consist of a series of round metal plates called platters, also called cylinders. They are coated with an electromagnetic material which can support magnetic states that are capable of being electrically altered. This means some type of electrical signal can alter the magnetic polarization of various areas of the plates. The state of these polarized areas can also be sensed. Each platter can hold large amounts of data. There are several platters mounted on a hard drive. Between each platter is a head which is used to sense and modify the states of the platter. There are two heads on each platter.

Each platter has data stored on it in a specific pattern for read and write access. The data is organized into tracks which are rings around the platter. The distance the head moves into the platter will determine which track is read. A sector is a section of data in the cylinder. Different hard drives have different numbers of sectors, tracks, and platters. The total storage space on the hard drive is traditionally equal to:
Sector size times sectors/track times tracks/cylinder times the number of cylinders.
With more modern drives, however, to increase storage space, some drives have more sectors on the outer tracks than the inner tracks. This is because there is more physical room for data on the outer tracks. Therefore this method of calculating hard drive capacity may not be effective in the future.

Controller Interface Types

A hard drive is a mass storage device where your operation system is installed along with many data files. There are two types of hard drives with regard to the controller:

1. IDE - Integrated Drive Electronics. A controller based interface. If your primary concern is low price with reasonable performance IDE is a good choice. It is still the most popular controller interface because of price.
2. SCSI - SCSI uses a separate bus hooked to the system bus using a host adapter. It is a more expensive system than IDE, but is better built and has a great deal of flexibility. If you are considering running a server or high performance system, this is the best way to go. There are several types of SCSI interface, the primary characteristic being the width of the data transfer (how many data bits are carried over the cable at a time). The important item is to be sure you get compatible controllers with your SCSI device such as your hard drive or CD-ROM drive.

Most hard drives have three characteristics of main importance for performance.

1. Size - The size of the hard drive is expressed in terms of Gigabytes which is roughly 1000 Megabytes. It is difficult to buy a drive less than 4 Gb today. Typical size are 8 through 20 Gb.
2. Speed - The data output of a hard drive is primary limited by the amount of time it takes for the electromagnetic head to reach the data at specific locations on the drive. The primary factor of limitation is hard drive rotation speed. Common speeds today are 5400 RPM (revolutions per minute), 7200 RPM, and 10000 RPM. Considering price and performance, we currently recommend 7200 RPM hard drives.
3. Reliability - The other performance factor that is worth considering is reliability. This is expressed as mean time between failure (MTBF) The higher the number, the better. Look for this specification on the manufacturer's specification sheets for each product.

Terms

• ATA - AT Attachment. This term refers to the type of IDE drive. Others are Microchannel (MCA IDE) and XT IDE. The ATA interface was used in the early 80386 based computers.
• ATA-2 - Refers to Enhanced IDE or EIDE.

Computer Memory

Packaging

Memory chips are called DIPs which stands for Dual Inline Packages. They are black chips with pins on both sides. Some say they look like black bugs. To make memory installation easier than it was in the past, these DIP chips were places on modules. There are two main module types that memory comes packaged on today.

1. SIMM - Single Inline Memory Module. They may have DIPs on one or both sides and will have 30 or 72 pins. Today, they normally are available in the 72 pin size which supports a 32 bit data transfer between the microprocessor and the memory.
2. DIMM - Double Inline Memory Module. The modules have 168 pins and support a 64 bit data transfer between the microprocessor and the memory. Synchronous Dynamic Access Memory (SDRAM) is the type of memory that is found on DIMM packages. The term SDRAM describes the memory type, and the term DIMM describes the package. These modules are available in 3.3 or 5 volt types and buffered or unbuffered memory. This allows four choices of DIMM types. You should check your motherboard manual to determine the type of memory required. You should be able to find this information on the motherboard manufacturers website before buying the motherboard. The most common choice for todays motherboards is 3.3 volt unbuffered DIMMs.

To install these packages, you press them into the socket on the motherboard and latch them in with a plastic latch on both sides. Normally as the memory module is pressed into place the latch will automatically latch the module in place. This is the essential knowledge required to understand enough to buy and install memory on your motherboard. The following sections give further technical details.

DRAM Access

DRAM memory is is accessed in chunks called cells. Every cell contains a certain number of bits or bytes. A row, column scheme is used to specify the section being accessed. The cells are arranged similar to the following table.

ROW 1, COL 1	ROW 1, COL 2	ROW 1, COL 3	ROW 1, COL 4
ROW 2, COL 1	ROW 2, COL 2	ROW 2, COL 3	ROW 2, COL 4
ROW 3, COL 1	ROW 3, COL 2	ROW 3, COL 3	ROW 3, COL 4
ROW 4, COL 1	ROW 4, COL 2	ROW 4, COL 3	ROW 4, COL 4

When the DRAM is accessed, the row, then the column address is specified. A page in memory is considered to be the memory available in the row.

Types of DRAM

The term DRAM stands for Dynamic Random Access Memory. There are three common types of DRAM today.

1. FPM DRAM - Fast Page Mode DRAM. When the first memory access is done, the row or page of the memory is specified. Once this is done, FPO DRAM allows any other row of memory to be accessed without specifying the row number. This speeds up access time.
2. EDO DRAM - Extended Data Out DRAM. This works like FPO DRAM but it holds the data valid even after strobe signals have gone inactive. This allows the microprocessor to request memory, and it does not need to wait for the memory to become valid. It can do other tasking, then come back later to get the data.
3. SDRAM - Synchronized DRAM inputs and outputs its data synchronized to a clock that runs at some fraction of the microprocessor speed. SDRAM is the fastest of these three types of DRAM. There is a new SDRAM called DDR (Double Data Rate) SDRAM which allows data reads on both the rising and falling edge of the synchronized clock.

Another new type of DRAM is called RDRAM developed by Rambus, Inc. It uses a high bandwidth channel to transmit data at very high rates. It attempts to eliminate the time it takes to access memory. Synclink DRAM (SLDRAM) competes with RDRAM and uses 16 bank architecture rather than 4 along with other performance enhancing improvements.

Cache Memory

Cache memory is special memory that operates much faster than SDRAM memory. It is also more expensive. It would be impractical to use this memory for the entire system both for reasons of expense and physical board and bus channel design requirements. Cache memory lies between the microprocessor and the system RAM. It is used as a buffer to reduce the time of memory access. There are two levels to this memory called L1 (level 1) and L2 (level 2). The level 1 memory is a part of the microprocessor, and the level 2 memory is just outside the microprocessor.

Microprocessor

The microprocessor is the center of your computer. It processes instructions and communicates with outside devices, controlling most of the operation of the computer. The microprocessor usually has a large heat sink attached to it. Some microprocessors come in a package with a heat sink and a fan included as a part of the package. Other microprocessors require you to install the heat sink and fan separately. This is not a difficult problem, but can be a bit daunting when the buyer wants to make sure they get the correct parts to fit their microprocessor. Also the buyer needs to make sure they will get the motherboard that their microprocessor will work with. This section will explain some of the differences in microprocessors and ways to be sure your parts match.

Microprocessors and Mounting

The mounting method refers to the type of connection the microprocessor makes with the motherboard. The following table lists the various mounting packages and some of the well known microprocessors that are mounted for that package.

• Socket 7 - AMD K5, K6, Intel Pentium 75-200Mhz, IBM
• Socket 370 - Some Intel Celerons
• Slot 1 - Intel Pentium II, Pentium III, Some Celeron 266-533
• Slot II - Intel Xeon
• Slot A - AMD Athlon

The Socket 7 processors are becoming less popular. We recommend socket 370, through slot A microprocessors at the current time. The prices on Socket 370 microprocessors are currently very low considering the performance of the systems. I recently bought a Celeron 500Mhz microprocessor with 66Mhz sidebus for under $120 with a motherboard for $84. When buying a microprocessor, make sure you get the type of socket you think since some processors are made for different sockets such as the Celeron. Be sure of one of the following.

1. The socket type is stated at the vendors website.
2. There is a microprocessor part number stated at the vendors website that can be traced to the manufacturers website which specifies the mounting package you want.

It would be no fun to get a Slot 1 motherboard and a socket 370 Microprocessor.

Microprocessor heat sinks and fans.

Being sure you get the correct heat sink and fan for your microprocessor can be a bit daunting. Who wants to get a $300 microprocessor, and risk it with an incorrect mounting of a heatsink or fan? Who wants to find out that they have purchased the wrong heatsink for their processor and spend days or weeks trying to sort it out? My solution is to purchase the microprocessor with the heatsink in the same package. Usually you get a better warranty and return policy this way and you don't need to worry about whether the two are compatible. I do not believe you can save enough money buying the heatsink and fan from anyone other then the vendor selling the microprocessor because of the time it takes for the additional research required and the potential trouble. The best solution to this problem is simply to buy a slot1, slot II or slot A microprocessor with the package that includes the fan and heatsink. These would be one of the Pentium II, Pentium III, Athlon, or Xeon packages. All that is required in this case is to slide the microprocessor carefully into its slot. With the exception of processors such as the Athlon which have a larger heat sink, requiring an extra plastic clip mechanism to help stabilize the heatsink, it is easier to install one of these processors than it is to install the computer's RAM memory or a hard drive.

Motherboard

The Memory Slots Yes, the motherboard is the mother of all boards on your computer. The motherboard may have a form factor of AT or ATX. We recommend you use ATX motherboards with ATX cases since this is the newer alternative and most modern microprocessors run on ATX motherboards. The motherboard holds the microprocessor, the memory, and several card slots. The memory may be SIMM sockets or DIMM sockets. The current standard is DIMM socketed memory. This is usually 168 pin 3 volt unbuffered synchronous DRAM memory. PC100 or PC133 memory is the current memory of choice. Most boards have 3 or 4 memory slots, which may, depending on the size of DIMM used, allow up or beyond 1 Gb total system memory. Most boards commonly allow 384 to 512 Mb of system RAM. The expansion bus The card slots are used to put additional cards such as video cards, sound cards, internal modems, or network cards into. Some motherboards today include video and sound without the addition of a extra card. These cards slots today are mostly PCI type card slots. When talking about cards that are plugged into a PC you are talking about the expansion bus. The expansion bus is a means of a microprocessor extending its communication ability further into the outside world. It is a data exchange means between add on cards and the microprocessor and the motherboard. There have been several types of expansion buses. ISA - Industry Standard Architecture. Used when the original 8088 8bit microprocessor based personal computers were produced. EISA - Extended ISA used when the 80286 through 80486 series microprocessors were being produced. This bus is still used but is being phased out and is almost gone today. MCI - Microchannel architecture by IBM and used mainly on IBM brand computers. PCI - Peripheral Component Interconnect. The popular expansion bus of choice. It is significantly faster than EISA. AGP - Accelerated Graphics Port. This bus is developed for fast video cards. It is currently up to 4X mode speed. The current popular expansion bus is the PCI (Peripheral Component Interconnect) bus for all cards except the graphics cards. For graphics cards, the bus of choice is AGP. Most motherboards today have one AGP slot and several PCI slots. Your expansion cards will plug into these card slots. Be sure you get cards that match the available type of slots on your motherboard. My microprocessor runs at 500Mhz and my memory runs at 100Mhz. Why? As PC technology grew, eventually the access speed of the memory could no longer keep pace with the increased speed of the microprocessors. At this point, an I/O cache was placed on the microprocessor to be a buffer between the external memory on the motherboard and the internal processor registers. The memory was set to run at a different "side bus" speed which is some fraction of the microprocessor speed. Therefore when the speed of the microprocessor is set, it is set to some multiple of the side bus speed. In the case of a 500Mhz processor and 100Mhz PC100 capable memory, that multiple is 5. Sometimes this multiple and the sidebus frequency is set using jumpers on the motherboard, or it may be set with auto detection and the BIOS. You will need to consult your motherboard manual to determine how to set these parameters. Other motherboard items Other items on your motherboard that you should be aware of are the small pin connectors that are used to connect the following controls and indicatory to your motherboard. Power supply switch. Reset switch The power on indicator. Hard drive activity indicator. In the case speaker connector.

Inside the Computer

Opening the case

Warning! Before deciding to open your computer case and touch or remove any parts inside, you should be aware that your body can contain static electricity that may be discharged to the circuits inside your computer. A static discharge can damage or ruin your computer. Therefore prior to doing any work inside your computer, you should get a grounding strap. A grounding strap can be attached to one of your wrists and be plugged into the wall (if it is the type made for a wall outlet). If you don't have the ground strap made for the wall outlet, you may need to attach your ground strap to a cold water pipe. A ground strap grounds your body using the earth ground in the wall outlet or from a cold water pipe. A grounding strap should cost less than twenty dollars and should be available at an electrical equipment store. You should always wear a ground strap when working inside your computer case. Especially when working with the microprocessor, memory, motherboard, or other plug in boards.

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Warning! Hazard! Prior to opening your computer case, be sure it is turned off and unplugged. 110 volts can cause injury or death! Also working on your computer while it is plugged in can damage or destroy it.

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To open the computer case, depending on the type of case you may need to follow one of the following sets of instructions.

• For the less expensive cases normally you need to:
  1. Remove 4 or 5 screws in the back of the case. Be sure these screws hold the case and not some other component like the power supply.
  2. Slide the case foreword on its slots and remove it.
• For higher quality cases
  1. Remove one thumbscrew or one or two phillips head screws from the back of your case that may hold one or more panels.
  2. Remove the top panel and/or one or more necessary side panels.

Once you have opened the case, lay it on its side so you can look at the inside components. You should see some variation of the following picture.

In the picture, the front of the computer is at the bottom and the rear is at the top. At the front (bottom of the picture) are normally two metal bays made to enclose hard drives, floppy drives, and CD-ROM drives. There is a 5.25 inch and a 3.5 inch set of bays. Most hard drives will mount into the smaller 3.5 inch bays with the CD-ROMS mounting in the 5.25 inch bays. The hard floppy, and CD-ROM drives are mounted to their enclosures with screws on their left and right sides. The power supply is on the top right side of the picture which when the computer is in its normal standing position is the top rear. At this location it will draw the warm air that naturally rises to the top of the case to the outside.

Cables

Between the hard, floppy, and CD-ROM drive bays you will see some thin flat grey cables going to the floppy and hard drive connectors on the motherboard. These are data/control cables used by the system to control the drives and get and send data from and to them. On one side of the grey cable should be a red stripe going along the cable. This red stripe should always be placed on the pin 1 side of the connector. You will need to look closely at the connectors on your hard and floppy drives to determine which is the pin 1 side or read your manual. On hard drives and most CD-ROMs pin 1 is on the side closest to the power supply connector.
Cables running between the power supply are colored black, red, and yellow. There is one going to each hard drive, floppy drive, CD-ROM drive and any other drive the system is using such as a mass storage device. There is also a multicolored power supply cable with about 12 wires going between the power supply and the motherboard. The wires are colored black, red, yellow, orange, and there is one that is blue. The connector on this cable should be keyed so it cannot be inserted the wrong way. Also some of the data cables are keyed, but others are not. It varies a little from system to system.

The power supply

The primary rating on the power supply that you should be concerned about is wattage. Most are standard in the range from 230 through 300 watts. I recommend 250 watts for most standard systems today. If you are buying a high powered system with a microprocessor that uses a lot of power such as an AMD Athlon, you will need to buy a case that has a power supply capable of providing 300 watts.
The following sections talk about the motherboard and associated components such as memory, the microprocessor, and the expansion cards.

Computer Cases

There are two basic styles of cases the computer may come assembled in. They are basically tower and desktop style cases. Desktop style is in the shape of a rectangular box, that sets flat on a desk. Usually the computer monitor is placed on top of it. A tower case, looks similar to a tower as the name says. These computers will be placed off to the side of the keyboard and monitor. The tower case is the most popular style of desktop computer today. It is also recommended by some microprocessor manufacturers since it can be designed for better heat dissipation. Tower cases come in several sizes which are: Mini-tower - The smallest. Mid-tower - The standard size, recommended for most applications including standard desktop systems and some servers. Full-tower - The largest. Usually this is a very tall case and you may have a difficult time fitting it where overhead is limited. This case is usually used for high powered servers. Looking at the front of your computer, you see the front panel: The exact locations of many of these items vary somewhat from computer to computer, but the overall layout is generally the same. Types of cases come to fit AT and ATX sizes. If you want a modern computer, you will want, or should have an ATX case. The AT or ATX version refers to the type of motherboard the case is designed to fit. The AT case is for the old type of motherboards such as for the 80486 microprocessor based computers. Definitions Pin - A part of a connector that extends outward to extend into and make contact with a socket. Referred to as the male side of a connector. Socket - a part of a connector that contains an internal contact to receive the extended side (pin) of a connector. Referred to as the female side of a connector. Jack - A receptacle where power of signal connectors may be plugged into. These are usually on the case of a computer or the motherboard and are made to receive plugs from devices such as keyboards. Plug - The part that connects with the jack, which comes from a keyboard, mouse, monitor or other device. This is the side associated with a cable. The Back Panel The back panel includes two power connectors. One is to connect your computer to the wall outlet, and the other can be used to connect the monitor power to operate from the socket on the back of the case. Usually the power connector for the monitor is not used since many use a power strip or a surge protector to control the power to all devices. The keyboard and mouse connectors are both normally PS2 connectors on new computers. There are two sizes of PS2 connectors, Normally with today's equipment you will want the smaller PS2 connector on your keyboard. Mice don't come with the larger PS2 connector. There are adapters made to allow smaller connectors to adjust to a larger sockets and vice-versa. A PS2 connector is a round connector with 6 pins and a plastic key. The keyboard always uses the PS2 connector, however the mouse may be a serial mouse and may plug into the serial cable on your computer. With modern computers, normally a PS2 mouse will be used. Near the keyboard and mouse connectors is normally a connector for a parallel printer. This is what is called a parallel device, meaning that more than one line carries data in one direction at a time. This is the connector you will plug your parallel printer into. See your computers motherboard or owner's manual for exact placement of these connectors. Usually a little below the parallel printer connector are two serial connectors. There are two types of serial connectors, which are called DB9 and DB25. One type, DB9 contains 9 pins or sockets and the other contains 25 pins or sockets. You may have any combination of the 9 or 25 pin connectors. Also some are female style connectors, and others are male. You will need to make sure your connectors match for their given types. The serial cables are normally used to connect a serial mouse, an external modem, or some other device to your computer. Below the parallel and serial connectors are a series of slots which are covered by a metal plate. This is where additional cards are plugged into your system. These cards are usually a video card, a sound card, internal modem, and one or more network cards. Your monitor connector would plug into a connector on your video card, and your speakers will plug into a connector on your sound card. See your sound card and video card manual for exact placement of these connectors on the card. These cards are plugged into the motherboard and you must open your case up to remove or add one of these cards.

Computer Components

Computers come in all types and sizes. There are primarily two main sizes of computers. They are:

• Portable
• Desktop

The portable computer comes in various sizes and are referred to as laptops, notebooks, and hand-held computers. These generally denote different sizes, the laptop being the largest, and the hand-held is the smallest size. This document will mainly talk about the desktop computer although portable computer issues are also discussed in various areas.

Computer Components:

Computers are made of the following basic components:

1. Case with hardware inside:
   1. Power Supply - The power supply comes with the case, but this component is mentioned separately since there are various types of power supplies. The one you should get depends on the requirements of your system. This will be discussed in more detail later
      
   2. Motherboard - This is where the core components of your computer reside which are listed below. Also the support cards for video, sound, networking and more are mounted into this board.
      1. Microprocessor - This is the brain of your computer. It performs commands and instructions and controls the operation of the computer.
      2. Memory - The RAM in your system is mounted on the motherboard. This is memory that must be powered on to retain its contents.
      3. Drive controllers - The drive controllers control the interface of your system to your hard drives. The controllers let your hard drives work by controlling their operation. On most systems, they are included on the motherboard, however you may add additional controllers for faster or other types of drives.
   3. Hard disk drive(s) - This is where your files are permanently stored on your computer. Also, normally, your operating system is installed here.
      
   4. CD-ROM drive(s) - This is normally a read only drive where files are permanently stored. There are now read/write CD-ROM drives that use special software to allow users to read from and write to these drives.
      
   5. Floppy drive(s) - A floppy is a small disk storage device that today typically has about 1.4 Megabytes of memory capacity.
      
   6. Other possible file storage devices include DVD devices, Tape backup devices, and some others.
2. Monitor - This device which operates like a TV set lets the user see how the computer is responding to their commands.
   
3. Keyboard - This is where the user enters text commands into the computer.
   
4. Mouse - A point and click interface for entering commands which works well in graphical environments.

Computer Tricks - Microsoft Office Tricks

Microsoft Office, being the most common office suite, has some really useful and computer tricks that can be used. Here are a few good ones:

• Mousewheel Zooming in WordSick of clicking manually on the zoom drop down all the time? No problem! Hold down the Ctrl key and scroll with your mouse wheel... pretty neat huh? The page zooms in and out based on the direction you move the mousewheel. This also works in most modern web browsers which is incredibly useful if you have short sight problems etc. Computer tricks don't get much better than this!
• Save All and Close All in WordSometimes when you have a ton of documents open that you wish to save, or perhaps they are becoming overwhelming and you wish to close them all, you can hold down the shift key then click on the file menu. Two new options appear which are 'Save All' and 'Close All'. Click as appropriate.
• Increase font size in Word with a keypressHolding down ctrl and shift while press the '<' or '>' keys (they operate as a comma and period normally) the font size of the selected text will grow and shrink as specified. This can be handy if you aren't sure what specific font size you want and wish to 'see' what looks good without having to enter or select any numeric size values. I find myself using computer tricks a lot but this one is used rather frequently now that I am used to it.
• Instant new worksheet in excel
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  By holding shift and pressing F11 a new worksheet is instantly added to your excel file. This saves a ton of clicks! After the key combo is pressed the new workbook instantly becomes the active one making it double handy.
• Create a new document in any office applicationI should mention that this key press also works for a large range of software packages including the browser you are using right now (don't quote me on that though!). Holding Ctrl and pressing N results in a new window opening for the currently active software application. Give it a try!

Computer Tricks - Computer Optimization

Are you keeping on top of the general maintenance of your computer? Here are some computer tips to optimize your computer's performance:

• Temp folder cleanup
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  The temp folder found in C:\Windows\Temp often contains files that have no reason to exist any longer. The folder is used by a large number of programs to store temporary files but unfortunately due to lazy coding the files often remain afterwards leading to a massive amount of data filling up the temp folder over time.
  You can use the 'Disk Cleanup Wizard' that comes with windows to sort out your temp folder by clicking on the Start menu then clicking on Programs > Accessories > System Tools > Disk Cleanup. Select the drive you wish to clean (usually C:) and then after a while of loading a dialog box will appear with recommendations. One of my favorite computer tricks when my computer starts to get a bit sluggish.
• Remove old programsMake sure you keep on top of your installed software. The Add/Remove Programs tool allows you to do this. Click on the start menu then settings then control panel. In the window that appears double click on 'Add or Remove Programs' and a dialog will appear after a short time. Any software you do not actively use be sure to get rid of it. This will save disk space, prevent any future software conflicts and hide the fact you installed a naughty program from friends or family!
• Make sure you keep on top of what you have installed and remove unused software
• DefragmentOver time a hard disk gets a bit sluggish due to being fragmented. It occurs every time the system struggles to store a whole file (generally big files) so it slots bits of the data in between other files. To make the files whole again you have to perform a defragment. Click on the start menu then programs then accessories then system tools then 'Disk Defragmenter'. Depending on disk size it can take several hours to complete so perhaps go and watch a film while it works, something like the Matrix is good! Another one of my favorite computer tricks because it feels like my hard disk is 'purified' afterwards.

Computer Tricks - Shortcut Keys

A few great shortcut keys that are great computer tricks are:

• Hold the windows key and press M
  Lock your computer in one keypress from intruders and nosey people!
  This will minimise all windows in one key press! This is the same as pressing the 'Show Desktop' icon but without having to click on it. It should be noted that Windows key + D also works for this!
• Hold the windows key and press L
  This will lock your workstation instantly. This means that if you are in a public place or a shared machine and go for a toilet break but do not wish for anyone to sneak a peak at what you are doing, or at worst steal your files, then this will take you back to the login screen instantly. Very handy indeed!
• Hold alt then press F4
  This is quite a common one but should be mentioned here anyway. This key press will close your current window. If your screen is getting cluttered you can go on a 'close rampage' by holding down the F4 key as well! Good times!
• Hold ctrl then press F4
  The junior brother of alt F4. Instead of closing the whole window this will close internal windows within the current program. For example if you have multiple windows open in one instance of Microsoft Word this will close them one at a time. The best part is this works for the tab browsing that has come in to play in recent browsers. The key press closes the active tab you are viewing! This is one of the best computer tricks I find when browsing as it is really effective for FireFox for closing tabs.
• Hold alt and press tab
  This will cycle between programs on your computer. This feature isn't that useful until you install this nice little Microsoft tool which will show a thumbnail of the program your about the switch to. If you don't wish to activate the selected program keep holding down alt and press tab again to cycle to the next one!

Holding the windows key and pressing break is one of the lesser known but more useful keypresses!

You can set up custom shortcut keys via this field in the properties of any shortcut!

• Hold the windows key and press break
  A lesser known shortcut but still useful! This one will open the System Properties dialog window which displays your RAM etc.
• Hold the windows key and press EThis will open 'My Computer' in explorer style mode. This is very handy if you want to access your files and disk drives from anywhere without having to find the icon on the desktop or start menu.
• Custom Shortcut Keys!
  Another lesser known trick is setting up your own custom key presses. This works for a per-program basis. To setup a shortcut key to your favorite program first you need to right click on the shortcut icon you commonly use and then press on properties. Click on the Shortcut' tab and there will be a text field called 'Shortcut key'. Simply click in that and enter the key press you wish to use. Press OK and that key press is permanently associated with that program. This is very handy for many things such as opening word or opening your favorite game!

Computer Drivers Why you need them, where to get them

Computer drivers are software programs that are made up of a specific set of instructions that communicate with the operating system on how to run and use a piece of hardware that is installed in the computer system. 

For each piece of hardware that is installed on your system, you will require a specific drive to instruct it. Examples of hardware that require drivers include audio/sound cards, video cards for monitors, printers and modems. 

Should you load the hardware and fail to load the right driver, the equipment will not know how to talk to the computer in order to function. By installing the driver software, the equipment will instantly know where it needs to connect and what components of the computer it needs to talk to. 

It Worked Before, Why Not Now?

Drivers are pieces of software and just like any other piece of software are susceptible to corruption, hence they may at times, fail to perform. When this occurs you might need to head to the manufacturer’s website and update your drivers. 

Sometimes you may also need to update your drivers when the manufacturer brings out a new version. Manufacturers are constantly updating drivers but they cannot send out drivers to everyone who has ever purchased a product. As a result it is important that you regularly check the sites of products you own to see if updated drivers have been released