Desktop Computers


Computers come in all shapes and sizes. Some are portable, some are beautiful and some are very powerful. With so many different computers to choose from, selecting the right one can be confusing. This buyer’s guide will help you sort through all the confusion so you can buy exactly what you need and not waste money on features you don’t need.

Keep in mind that most people do not need a “state-of-the-art” system. Our editor even admonishes us against using the phrase. If you’re currently using a computer that’s more than five years old, a new entry-level system will blow it away in terms of performance, memory and storage space. Unless you're busy with video editing and encoding, 3D modeling, geophysical surveying and other processor-intensive applications, a basic computer is powerful enough; Web surfing, email, productivity apps and basic multimedia don’t present much of a workload. For perspective, consider that only 10 years ago, the typical PC contained a 500 MHz single-core processor, maybe 256MB of memory, an 8GB hard drive and a CD-ROM drive. Operating systems and applications haven’t really changed much since then.

Should I buy PC or Mac?

PCs are the bread and butter of the computer world. There are hundreds of models on the market and many of them are very affordable. Macintosh computers, or Macs, on the other hand, have an elite following of people who are willing to pay a premium for the finely crafted machines. There’s also tighter control of software applications and hardware accessories, which tends to make the Mac platform very stable, thereby justifying its niche market. Macs are generally the computer of choice for photographers, videographers, musicians and graphic designers because the Mac operating system is better suited to running applications appropriate to those professions, so if you’re in those fields you’re probably better off using a Mac.

Macs also have a unique appearance, which is reason enough for many users to purchase them. But if you can help yourself, you shouldn’t buy a computer based on appearance. Instead, pay more attention to the operating features you want at a price point you can live with. Don’t shop by brand name, either. More important are the hardware specs, fit and finish, feature set, ergonomics and price.

The basic difference between a PC and a Mac is the operating system. The operating system is the software that runs when you turn the computer on. Practically all PCs, as of this writing, come with Windows 7 and all Macs come with OS X. Both operating systems are easy to use, but if you are already familiar with one of them then you should probably roll with the one you know.

From this point forward, we won’t make a distinction between PCs and Macs. You’re probably already set on one or the other, so just use this guide to help select the features that will make a difference.

What’s inside a computer?

All computers contain a motherboard, which is a circuit board that makes all the electrical connections between the components that are soldered to it. One of those components is the central processing unit, or CPU for short. The CPU is the “brains” of a computer. The CPU runs the operating system and other software applications, executing whatever instructions are requested.

CPUs process data and they need to store and retrieve information temporarily in order to work properly. This temporary storage is called RAM, Random Access Memory. RAM is primarily used when the computer is on and running different programs. The more RAM you have, the more applications you will be able to open, which allows you to multitask seamlessly.

Computers also need to store information for a long period of time, such asdocuments, photos, music and videos. This long-term memory storage usually comes in the form of a hard disk drive, or hard drive, for short. A hard drive is a sealed unit containing magnetically coated metal disks that spin at high speed and heads that move back and forth across the surface of the disks to read and write information from and to them. Newer models can come with a solid-state drive, which uses microchips in non-volatile memory chips and has no moving parts. Solid-state drives are more reliable and transfer data at a faster rate, but are much more expensive than their hard disk drive counterparts.

It should be noted that RAM only stores system memory, such as information for applications and operating systems, and not data, such as documents or photos. Also, RAM only stores information while the computer is on and resets after the computer is restarted. Hard drives are where you store your documents, photos music and videos. These will stay on your hard drive, even after the computer has been turned off and rebooted. 

Most computers also contain an optical drive, the most common of which is a DVD burner. An optical drive uses a laser to read data from CDs, DVDs and sometimes Blu-ray discs, and the burner part means that it can write or “burn” information to blank discs.

What are desktop computers?

As the name implies, desktop computers are meant to be set up and used on a desktop. They have to be plugged into an AC outlet in order to function. Because of their size and weight, desktop computers are less likely than notebook computers to be stolen.

Desktop computers don’t usually come with monitors, so you’re free to select whatever size, color quality and price range you like. Desktop computers do, however, usually come with a full-size keyboard that offers typing comfort. If you’re not happy with a particular keyboard, you can always swap it out for one that you do like and even go wireless if you would prefer to use your computer from a distance. The same can be said of the mouse. With a notebook computer, you’re stuck with whatever keyboard comes attached. Also, a notebook computer will typically have a touchpad and not a mouse, which may make navigating the screen difficult, especially for a novice.

What are compact desktop computers?

Big, boring beige boxes come to mind when most people think of a desktop computer. But technology evolves. Today, desktops are far from boring―and they’re usually black, not beige. They’re not always big. You can buy super-compact desktop systems that take up very little space on your desktop.

Compact desktop systems have little or no room inside for cooling fans, so they typically use low-power components that generate very little heat. These low-power components are the same as those used in compact notebooks or netbooks and they’re not very powerful. But they’re fine if all you need to do is get online, browse the Web and check email. They’re also fine for running applications such as Microsoft Office. Some compact desktops don’t include optical drives, so you’ll need to purchase an external USB optical drive if you need one.

Compact desktop systems cost between $300 and $500. They typically feature Intel Atom processors, integrated graphics, 2GB of memory and a 250GB hard drive. Gigabit Ethernet and 802.11n Wi-Fi are usually present, so you can connect them with an Ethernet cable to a wireless network.

If you think you might ever need to expand your desktop system or add more components to it, then consider larger desktop computers. The compact desktop units don’t have any room inside to add more hard drives, RAM modules, graphics cards, Blu-ray drives or any other compnents.

What are all-in-one desktop computers?

If a compact desktop system still leaves more clutter on your desk than you would like, then consider an all-in-one desktop computer. An all-in-one desktop computer typically has the computer built right into a monitor so it looks like all you have is a monitor, keyboard and mouse.

All-in-one desktops are very easy to set up, and you don’t have to worry about buying a monitor. All you have to consider is the size of the screen and the components that are included. In a nutshell, though, most all-in-one desktops contain low-end hardware and have no room for expansion. For practical purposes, if you think you’ll ever need to upgrade your computer, then you need a full-size desktop computer.

What are full-size desktop computers?

Classic, full-size desktop computers consist of the computer tower, along with a separate monitor, keyboard and mouse. Unlike notebooks and compact desktops, full-size desktops have plenty of room inside for expansion purposes. Whether it’s a second hard drive, a  second graphics ca, a Blu-ray drive or even a floppy disk drive (which is nearly extinct but might be needed to read data off a bunch of old disks), a large desktop system has the room to add it.

Desktop systems are the most powerful computers you can buy because they can support the fastest, most powerful processors available. But, the faster and more powerful a processor is, the more heat it generates. The faster a hard drive spins the more heat it generates. And the more memory modules you install in a system, the more heat they will generate. That’s why full-size desktop systems have one or more cooling fans inside to blow the hot air out and draw cool air in.

If there’s a particular software package you need to run, find out the type of processor, amount of memory and size of hard drive that’s recommended and try to meet those requirements in your new system. If you simply want a new system that will do something faster than your old one, like encoding video, then just shop by price and buy the fastest system you can afford.

Every component you add to a desktop system puts an additional load on the power supply. Small, inexpensive desktops have low-wattage power supplies; say 250 watts or less, while high-end systems with lots of expansion bays will have high-wattage power supplies that might be larger than 500 watts. You shouldn’t concern yourself with the power-supply wattage unless you plan on adding lots of peripherals and accessories to your desktop system.

Unlike notebooks and compact desktops, where you’re stuck with whatever components they come with, full-size desktops have always allowed you to change various elements. Depending on the motherboard, you can often install a faster CPU. And if you can’t, you can always install a new motherboard that does allow a faster CPU. If a new game comes out that requires a particular graphics card, you can always install it. Gamers typically use desktop systems because they’re so easily upgradeable. Should you load up a desktop computer with more components than its power supply can handle, you can always install a more powerful power supply.

Most desktop systems have audio-processing circuitry and inputs and outputs integrated into the motherboard. All you have to do is connect speakers and a microphone if needed. But if you’re really into audio or use your computer for home recording, you’ll probably want an add-on audio interface card or USB peripheral and more advanced software than what the operating system offers. The same goes for video; if you want to work with video on your computer you’ll want an accessory video-capture card with the specific capabilities you’re after. Either that or purchase a desktop system specifically tailored for video capturing and editing.

What should I know about graphics?

A Video Graphics Array, or VGA connector, is the oldest type of graphics connector still used in computers. Any new computer monitor and most graphics cards will, at the very least, feature a VGA connector. A VGA connector carries 15 pins arranged in three rows. Notebook computers often have a mini-VGA port instead of a full-sized VGA connector. If you have an older display with a VGA connector that you want to use with a new computer, just make sure the new system has a VGA output.

Most new flat-panel displays feature a Digital Visual Interface, or DVI connector, which was designed to replace VGA connectors. Even so, many new displays feature both DVI and VGA connectors. If you have a monitor with a DVI connector that you want to use with a new system, just make sure the new system has a compatible DVI output.

DisplayPort is another digital display interface that’s common on Macs. Like DVI, if you have a monitor with a DisplayPort connector that you want to use with a new system, just make sure the new system has a compatible DisplayPort output. Unlike DVI or VGA, DisplayPort can transfer both video and audio signals at the same time through a single connection, minimizing your need for multiple cables.

HDMI (High-Definition Multimedia Interface) is also designed for digital video and audio transmission. HDMI is far more common on set-top boxes and HDTVs than on computers. Even so, if you want to connect your new computer to your HDTV, make sure the computer has an HDMI output.

What should I know about processors, memory and storage?

There are so many different processors to choose from that selecting one can be daunting. But there are a couple of good rules of thumb you can follow. When a new processor becomes available, you have to pay a premium for it. Only when time is money and cost is no obstacle should you go for the very latest processor. That’s because once a processor has been available for a while, prices start to drop and you can get leading-edge performance for a lot less money.

A good way to compare different processors is to look at the clock speed and the number of cores. Each core is basically a separate processor, and the clock speed determines the speed at which each core runs.

Instead of trying to figure out what processor is best, just determine which features you need to have in a computer system and how much money you want to spend, and then buy the system that has all the features you want and the fastest processor you can afford. After all, you can never keep up with technology. Even if you buy the fastest thing out there today, within months there will be something even faster.

The same principle applies to memory. Every year, computers come with more memory than they did the previous year, even though the things that people do with computers don’t change much from year to year. 4GB of memory is more than most people will ever need.

Most new computers come with Serial ATA (SATA) hard drives, which are fine for just about everyone. Only if you can economically justify the cost should you opt for the faster Serial Attached SCSI, or SAS drives, which are typically found in high-end workstations. Solid state drives are the latest in hard drive technology and are more reliable as well as faster than their hard disk drive counterparts, but you’ll be paying a premium for them. Most entry-level systems come with a 250GB hard drive or larger. If you’ve never filled up a smaller hard drive, then 250GB will do you just right. If you’re always looking for more disk space, it makes sense to pay a bit extra for a 500GB or even a 1TB hard drive.

What about expanding my computer’s capabilities?

A desktop computer motherboard has slots on it that allow you to install expansion cards to add new functionality or improve performance. A card installs in a slot in such a way that its bracket and connectors face the outside rear of the cabinet. PCI slots have been around for years, but new systems still have them. PCI slots let you install older compnents in new computers, or even new components that still have a PCI interface.

The latest type of expansion slot is called Peripheral Component Interconnect Express or PCI Express for short, or PCIe for even shorter. There are different sizes, or widths, of PCIe slots: x1, x2, x4, x8, x16 and x32. The most common sizes are x1 and x16. Depending on the type of expansion card you are installing, it will need a certain size slot, or one that’s larger. A PCIe x1 slot is the smallest and it’s designed to accept simple expansion cards that don’t need to transfer huge amounts of data to and from the motherboard. The larger x16 slots are typically used for high-end graphics cards that need to quickly input huge amounts of data, then process it in real time and pass it on to the monitor. Basic graphics cards are typically integrated, or built, into the motherboard.

An x1 card will fit in an x1, x2, x4, x8, x16 or x32 slot. An x2 card will fit in an x2, x4, x8, x16 or x32 slot and so on. But you cannot fit an x16 card in an x8 slot, nor will an x2 card in an x1 slot be made to work. A larger slot sometimes contains the electrical connections of a smaller one. For example, an x8 slot might have only x4 contact compatibility, so that an x8 card will fit in the slot but function at the x4 limit. Note that x32 slots do exist, but you won’t see them in today’s computers. You might see them in the future, unless a better technology comes along that makes them obsolete.

The motherboard inside a middle-of-the-road desktop system might contain two PCI slots, one PCIe x1 slot and one PCIe x16 slot, whereas a high-end system might contain three PCI slots, one x4 slot, and two x16 slots. If there’s a specific expansion card that you want to install in a new desktop system, just make sure that the system has at least one such slot. If you have nothing specific in mind, then just buy a system that has a good variety of expansion slots and when the need for an expansion card arises, buy a card that will fit one of the slots you have.

Expansion slots will allow you to install the latest USB 3.0 adapter card if your system doesn’t already have USB 3.0. You could also install a video-capture card, the latest network card, FireWire, the latest graphics card or a TV tuner. With a TV tuner, a big hard drive and an HDMI output you have the makings of a custom-made DVR.

If you have no specific needs but are interested in buying a desktop system because of its expandability, there are a few things to look for. Look for plenty of USB ports on the front and rear of the chassis. You’ll need three rear USB ports just for a keyboard, mouse and printer, so having at least four rear-USB ports will leave you with a spare one for some other peripheral down the road. It’s good to have at least two USB ports on the front of the chassis for USB keys, digital cameras and other convenience purposes. Look for a FireWire port if you have video gear or external; hard drives that use FireWire.

The Takeaway

  • A compact desktop or, even better, an all-in-one desktop are great if space is limited.
  • A compact desktop or all-in-one desktop are most appropriate if you will never have to add more components to the system.
  • Get a desktop computer if you already have a monitor that you want to use, or if you want to be able to upgrade your monitor in the future.
  • Get a desktop computer if there’s too much risk of notebook computers being stolen.
  • Purchase a full-size desktop computer if you want to be able to add more hard drives, optical drives or other compnents to the system.