| |
Hi there! Are you in the market for a computer? If you want to know more about the technology
and trade of computer hardware, read this article.
The Processor
When considering what type of CPU (central processing unit) to buy for your new computer
there are a handful of specs that vary from chip to chip and can greatly affect the performance
of your machine.
First is the clock speed. Presently, CPUs are rated in GigaHertz (GHz, 2^30 cycles/second, or roughly
one billion cycles per second). A CPU's internal architecture works like a powerful calculator, and
performs a calculation for every tick of the clock. A 1GHz CPU will perform one billion computations
per second while a 2GHz CPU can make two billion computations each second. Not all chips are created
equally. Intel's Pentium 4 processors can perform at very high clock speeds, but the architecture of
AMD's Athlon processors allows them to perform more advanced computations per cycle. To level the playing
field AMD adds a number to the name of processor to indicate the equivalent Intel P4 clock speed.
Next is the front side bus (FSB) speed. Usually rated in MegaHertz (MHz, 2^20 cycles/second, or roughly
one million cycles per second), the front side bus indicates how often the CPU and motherboard can pass
information to each other. A faster FSB speed means the CPU can respond more quickly to input from the system
and return the results faster.
Third we have L1 and L2 cache, or on-chip memory. Processors come with a small array of RAM (random access memory,
we'll discuss system RAM a little later) built in. The L2 cache resides on the CPU outside of the microprocessor,
the L1 cache is incorporated within the microprocessor. A CPU can access the L1 cache faster than any other memory
in your computer. Next in line is the L2 cache. To access the main system memory, the CPU has to go through the
motherboard, and even further away are the sound and video memory. L1 cache is not generally promoted as a feature
of the chip but the specs are readily available. The L2 cache varies greatly from chip to chip, usually from
128 kilobytes (1 KB = 1024 bytes, 1 byte = 8 bits, a bit can hold a boolean value (0 or 1), thus a byte can hold a
value from 0 to 255) to 2 megabytes (1 MB = 1024 KB). The L2 cache serves as a half way point between the L1 cache
and the main system RAM. Larger L2 caches mean more information can be placed very close to the CPU for use,
and the CPU can execute commands much faster.
Lastly, you'll want to know about hyperthreading technology. This is a recent development (at the time this article was written, at least)
that allows a processor to behave like more than one processor. On today's multi-tasking workstations, and
substantially more so on servers, several applications run at the same time, often vying for the processor's
attention. Hyperthreading enables the CPU to allocate partial resources to each request, improving performance
whenever two or more applications are executing commands. Windows XP (Home and Pro) supports hyperthreading.
The Motherboard
This is my favorite component. The motherboard, or mainboard, enables all the components of your computer
to talk to each other. The motherboard has a socket to accommodate the CPU, slots for the system ram, IDE
controllers for your hard drives, floppy controllers for the floppies, PCI bus for upgrade cards, AGP controller
for your graphics cards, and may have a variety of other built in features.
If you're on a tight budget, this is not the place to skimp. A cheap motherboard may get your system up and
running but performance will be substantially lower than with a well designed motherboard. Of all the
manufacturers I've dealt with, MSI is my current favorite, offering a host of mid-to-high end workstation (desktop PC)
solutions.
When choosing a motherboard, make sure it has the appropriate socket for your CPU (e.g. Socket 478 up to
800MHz FSB, etc.). Also note what kind of RAM it supports and how much. If you prefer onboard graphics
or sound in lieu of a separate sound or video card, you can find a variety of motherboards with these features.
Random Access Memory (RAM)
Random Access Memory is a high-speed storage for information needed by running applications. Installing more RAM
in your machine means you can run a larger number of applications, or work with larger amounts of information more
rapidly. Sound, image, and video editing are some uses for your computer that are very RAM intensive. With a large
file (like a long movie or high resolution image), fitting more or all of the file into RAM will improve performance tenfold.
If less than all of the data can fit in RAM, the operating system uses the hard drive to store what's left, slowing
editing processes to a crawl. More RAM is always better, even if you rarely need the higher capacity.
Like the CPU's FSB, ram also has a refresh frequency. Frequencies are often displayed directly, like 266MHz,
but also appear as a PCxxxx rating. The higher the number, the faster the RAM. For example, PC2100 is not as fast as
PC3200. Be sure the clock speed of the RAM is supported by your motherboard.
The Hard Drive
This is your computer's warehouse. All the information you want to use on your computer is stored on your
hard drive. Hard drives vary by capacity (how much information can be stored on it) disk rotation speed,
seek time, and interface type. The most common interface is IDE, but you can also buy drives that
connect via SCSI, USB, IEEE1394, and other interfaces. Almost all motherboards have built in IDE controllers
and support IDE devices by default. The capacity of your drive can vary from 1GB (gigabyte) or less to hundreds
of gigabytes. If you need more storage space you can add hard drives to your system or buy drives with higher
capacity.
The rotation speed of the drive affects how quickly the drive can read and write data. A 10,000 RPM drive can read
and write its disks faster than a 7,200 RPM drive. The seek time measures the average time it takes for a drive
to look up a file. Faster seek times mean the drive can locate a spot on its disk surface (i.e. the start of a file)
quicker.
Video Cards
Video cards have a variety of stats. The most important being interface type. A video card can connect to your
motherboard through the AGP (accelerated graphics port) slot or a PCI slot. There are many AGP speeds, such as 2x,
4x, and 8x, and are sometimes not mutually compatible. If you buy an AGP graphics card, be sure the AGP port and speed
are supported by your motherboard. A video card can also connect via a PCI (peripheral component interconnect) slot.
PCI specifications rarely vary from the default and any PCI card should be compatible with your motherboard.
The amount of dedicated RAM built into your video card is probably the most advertised specification, from 1MB all
the way into the gigabyte range, more RAM available to your GPU (graphics processing unit) means faster rendering and
video compression computations. The bottom line is faster refresh rates during graphics intensive applications like
video games.
Rendering, shading, and filtering specifications are also advertised on high-end graphics cards.
Some video cards also offer TV In/Out connections and DVI (digital visual interface) outputs if you want to connect a TV
or digital monitor to your computer.
Sound Cards
Most sound cards are PCI devices. They range in features from basic sound outputs to Dolby 5.1 surround.
Cards may be compatible with a host of standards and interfaces that take the load off your CPU for
audio effects like echoes and compression.
Purchasing Options
Companies like Hewlett-Packard, Dell, and
Gateway offer complete computer systems at exceptional prices. Compared
to five years ago, the cost of assembled computers has gone down significantly in relation to the cost of
individual parts. The price of a base-model prefab machine is much cheaper than the cost of individual parts,
but a blazin' fast machine can be build for a lot less (and with better components) if you do it yourself.
Companies like NewEgg and ZipZoomFly
have excellent prices on components.
When comparing between building your own and buying from a computer manufacturer be sure to check the CPU's FSB
and RAM speeds. Don't forget to purchase an OEM (original equipment manufacturer) Operating System (like Windows) if you decide
to build your own.
|
|
|
|
