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Description of Desktop PC Terms

Case/PS

There are 4 main choices in case styles: Desktop, Mini-Tower, Mid-Tower, and Tower.

 

Desktops are designed be on a desk, with the monitor on top of the case. This usually places the monitor too high, however, and does not allow for proper cooling of the CPU. Mini-Towers are designed to be the smallest enclosure that can hold all your components, and be placed out of the way. Mid-Towers are designed for expansion, and for those that like a little more presence from their computer. Tower or Full-Tower cases are for servers where many hard drives and other components need be placed inside the case, or for those who require a looming presence from their computer.

For a typical system, 300 Watt power handling is adequate, more is better. Use power supply recommended by AMD or Intel as appropriate.

Hard Drive

Also known as storage. This is where the computer puts programs and information for permanent storage. Always buy as much as possible. The trend in software has been toward larger and larger application suites, so a good rule of thumb would be to think of the largest amount of storage you will need, then double that. Though on most systems, you can always add a second hard drive later if need be.

A faster hard drive can speed up many tasks on your computer. In general, hard drives that spin at a faster RPM rate are faster overall. The other main factor in a hard drive's speed is the time it takes to find a given piece of data, also known as "access time". A hard drive with a lower access time will usually be faster.

Removable Storage

3.5" 1.44MB is standard. Floppy disks are used for backups, transfers between computers, and software distribution. They should never be used as primary storage as they have failure rates hundreds of times higher than hard drives.

Zip Drives are another removable media drive. They perform the same function as floppy drives, but the disks can hold about 70 times more information. Their failure rate is much better than floppy drives as well, but they are still less reliable than a hard drive, so they too should not be used as primary storage.

CD-RW drives can function like floppy drives in most systems. In addition, the disks written with CD-RW can be read in most newer CD and DVD drives. They hold about 450 times more than a floppy when used as a backup device, and about 350 times more when used in the same manner as a floppy drive. Their failure rate is highly dependent on thier physical condition and care.

DVD+RW and DVD-RW are competing standards for rewritable DVD media. Both format's write-once media (DVD+R and DVD-R respectively) are generally compatible wtih older DVD readers, but they are not compatible with each other. At the time of this writing, DVD+R media was cheaper and more readily available. Many DVD writers can also read and write CD-R and/or CD-RW.

Optical Drive

This is necessary for loading many software titles, and can usually be used as an audio CD player as well. The x rating (e.g. 12x) is a measure of how fast the CD spins compared to an audio CD player.

New CD-ROM drives are starting to use constant angular velocity mechanisms (audio and older computer mechanisms are constant linear velocity). Therefore the data can be read faster at the edges of the disk as compared to the inner tracks. These newer drives will give either give a speed rating at the inner and outer tracks (e.g. 12-24x) or will give the outer track speed only (e.g. 20x Max). However, there is no standards body for CD-ROM drive naming, and several manufacturers add a few to the x rating. Access time and transfer rate are the most important aspects of CD-ROM drive. Lower is better for access time, higher is better for transfer rate.

Monitor

This is your primary feedback from the computer. Larger monitors are easier to read, and higher resolution monitors give you more places to put your multiple windows.

Most monitors are listed similar to this: 17" 1280x1024 .26mm

The first number is the diagonal tube size; the viewable size will be about an inch less than this.

The second number is the highest resolution that can be viewed at 60Hz vertical refresh. 60Hz vertical refresh is the same as a TV, but long term close viewing at this refresh rate bothers many people. It's a good idea to get a monitor rated one resolution bracket above where you really want so that you can view your chosen resolution at 72Hz or greater, the ergonomic standard for monitor refresh rates set by VESA. The resolution brackets are:

1600x1200
1280x1024
1024x768
800x600
640x480

The manufacturer might list a vertical refresh rate such as 1280x1024@72Hz instead, which would be fine for 1280x1024. Another thing to remember about resolution is that it's impractical to view higher than 1024x768 on a 15" monitor or 1280x1024 on a 17" monitor unless you put your nose 2" from the screen.

The last number is dot pitch and is a rough indicator of the quality of the tube. This number is the spacing between individual phosphors of the same color on the surface of the tube. Lower spacing is better, as small details will show better. .28 dot pitch is about the largest one should go on a standard mask monitor. For Trinitron or stripe mask screens, .26mm is the largest one should go since the stripes are rectangular and the measurement quoted is across the short side of the rectangle.

A new type of monitor that you might consider is the flat panel display.  This is essentially a laptop monitor that has been put into a stand-alone case for use with desktop systems.

Advantages to this type of display are:

  • Much lighter
  • Much thinner
  • "Digital" models have very sharp images, esp. with text
  • No flicker

Disadvantages are:

  • Higher cost per screen size (though this is falling)
  • "Digital" models require special video card
  • Only one built-in resolution.  Other resolutions look odd.
  • May be a few "stuck" pixels, just like a laptop

 Video Card

The video card can play a large role in the performance of your system. If you're looking for a good card, the two most important factors are chipset and amount of RAM.

The chipset of the video card is the card's brains. There are many out there and they all perform differently. It's best to look for at least a 64bit processor and some multimedia extensions built in to the card.  The chipset of a video card is more critical for game applications than business applications.

The amount of RAM determines how large an image you can display at a given color depth. 4MB is a common configuration, but for 3D effects, 8 MB or more would be useful.

You can usually look on the box of a video card to find out what combinations of video resolution, colors, and refresh rates it supports.

Keyboard

The keyboard, like the case and the mouse is a matter of personal preference. If possible, try out any prospective purchase first, or at least a very similar setup.

Sound Card

Sound Blaster compatibility is important if you wish to play games. For Windows system sounds or multimedia, any 16-bit audio card will do. For musical composition, a general MIDI (GM) wave table synthesis card is a must.   Newer systems should use PCI based sound cards. Newer games are taking advantage of 3D audio effects, which are aided by cards with 3D audio support.

Speakers

This is a matter of preference. Powered speakers tend to sound better than those driven by the sound card's amplifier. Three-speaker systems with a subwoofer tend to sound better than two-speaker systems.

Mouse

The mouse, like the case and the keyboard, is a matter of personal preference. If possible, try out any proposed purchase first, or at least a very similar setup. MS Mouse compatibility is a plus.

Operating System

This is the program that runs all the other programs you use. Windows operating systems have recently started to include many common applications as well.

Ethernet Card

If you connect through an Ethernet port, this is a must have item.

Modem

This provides network connectivity over the phone. 53/33.6 thousand bits per second (v.92 download/upload) is the fastest speed currently available.

Many modem alternatives are emerging. These include ISDN, xDSL, and cable modems. These new technologies are all faster and generally more expensive than a traditional modem. Contact your local phone company or cable provider to see if they are offered in your area.

Warranty

One year is standard. More is better.

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