Computer Chips Made Easy

Advertisements for computers do not make the buying decision easy.
All too often ads describe the system's microprocessor in such terms
as "2.80GHz Pentium 4 w/800MHz frontside bus/512K L2 cache." It's
confusing, but it does not have to be.

For starters, the "2.80GHz" is the microprocessor's clock speed.
That means its internal clock ticks a very speedy 2.8 billion times
per second. The importance of the clock speed is very much in dispute.
More on that in a second.

The "frontside bus" basically is a fast connection between the
microprocessor and system memory (random access memory, or RAM).
Both the microprocessor and RAM run faster than the usual circuits
inside the computer. So, the frontside bus adds another increment
of speed to the computer, which could be especially important when
playing games.

When you're buying, be sure the frontside bus is as fast as or faster
than RAM. Check the computer's specifications to learn the RAM's speed.

In addition to 800MHz, you will likely see frontside bus specifications
at 533MHz and 400MHz. But the computer's cost will go up or down with
the chip's clock speed, not the frontside bus. A 3GHz machine will cost
more than a 2GHz unit, regardless of frontside bus.

When you are working on your computer, the microprocessor is
constantly working on data. Not all of it comes from RAM. All
chips have level 2 cache, a pool of memory on or close to the
chip. The microprocessor attempts to guess what you'll need next
and stores that data in L2 cache.

The "512K L2 cache" in the ad above refers to this pool of memory.
Assuming the chip guesses correctly, having the data in L2 cache
helps the computer run faster. Chips also have L1 cache, which is
smaller. Again, it is used to speed the delivery of data to the
microprocessor. With cache, more is better.

Remember that "2.80GHz?" Intel traditionally has used clock speed as
a measure of quality. Advanced Micro Devices, whose clock speeds are
slower, has long argued that other aspects of the chip are more
important. AMD uses a designation of 2800+ to imply that its chip
is as fast or faster than the 2.8GHz Intel chip. Numerous tests have
shown AMD chips are generally as fast as comparable Intel chips. All
evidence indicates they work as reliably.

Apple chips' speeds are only about half as fast as Intel's, and
are also much slower than AMD's. But Apple claims its machines
are faster. Independent tests have shown that that is sometimes
true, and sometimes not.

All speed tests are laboratory measurements. Consumers may well not
see much speed difference between Intel, AMD and Apple. Many other
things inside computers, such as video systems and RAM, affect speeds
of individual machines.

All consumer microprocessors today are referred to as 32-bit.
That refers to the size of a piece of data the chip can process
at one time. (A bit is the basic measure of data.) The newest
major trend in computer microprocessors is 64-bit processing.

Doubling the amount of data a chip can handle will allow the data to
be more complex. Many servers today use 64-bit chips. But the first
consumer versions are due out in September with the AMD Athlon 64.

Software has to be written to take advantage of the 64-bit processing.
No 64-bit consumer programs are available today, but games will
probably be developed quickly. And AMD is working with Microsoft
to develop a 64-bit version of Windows.

Intel has a 64-bit chip also, the Itanium. It is not sold in consumer
machines. Apple refused to comment on any 64-bit plans, but may announce it soon.

--> MORE ABOUT ME--KIM:

You can read my weekly syndicated column in over 100 newspapers
across the country. I also host the three-hour weekend Kim Komando
Show. Every weekday you can hear my "Daily Computer Minute." I write
a weekly column for USA Today, too. Additionally, I write for MSN's
bCentral. One article I recently wrote for is "5 Tips and Tricks for
Using Word for Business." You can read it here online:
http://www.bcentral.com/articles/komando/127.asp

Return to Library of Business Information