Single, Dual or Quad Core: Which Is Best For You?

This is usually of absolutely no help to the average computer user who just wants the machine to run faster, knows they have to upgrade, and doesn't have a clue what a core does in the first place.

Therefore this article is for the entry-level crowd. The CPU Forum Gurus can just go back into their Silicon caves and not bother pointing out the oversimplifications as I'm not writing a white paper for AMD's Dr. Hector Ruiz.

At the beginning of personal computing there were various manufacturers of Central Processing Units (CPUs) which are the processors, or the brains, of your computer. Pretty well everything that is processed in your computer, with the major exception of the video processing, is done inside the CPU. That makes the CPU a very critical part of your system. Generally speaking, the faster your CPU can process the data, the faster your system responds and the less time you spend twiddling your thumbs and watching the hourglass.

These manufacturers started trying to top each other by making faster and faster CPUs. Most of them failed and went to join Cyrix in Silicon Heaven. Only Intel and AMD survived the shakeout, the former a $125 billion giant and the latter a $7 billion scrapper which held Intel at bay for several years with better, cheaper CPUs before developing a puzzling case of incompetentitis gravis in early 2006 and stumbing/delaying/screwing up all their new product launches.

Both Intel and AMD spent about a decade getting their silicon to go faster and faster until they both hit a brick wall around 2004. Current technology really wouldn't let the CPUs go above 4 GHz (a measure of processor speed in the cycles that they can process information). Any attempts to break the 4 GHz barrier resulted in steel smelter heat generation and nuclear powerplant electrical requirements.

Since Moore's Law states that computing has to double in speed every 18 months, engineering limitations be damned, there was no choice but to increase the number of cores in the CPU. This is analogous to taking a 4 cylinder engine out of your Chevy Vega and plunking in a 454 V-8 Big Block. Twice the number of "cylinders" should produce twice the "speed."

It didn't really work out that way, however. Taking a 3 GHz core and fitting it next to another 3 GHz core didn't process like a 6 GHz core at all. That's because the second core needs specific software to process at the same time. Processing data is like a single cash register queue. One bit has to follow the other. If you try to process one bit on this side and the next bit on the other side, the computer will get confused and process nothing at all, just like the cash register operator trying to serve two customers at once.

It turned out that less than 1% of all popular software applications could handle the second core. The ones that could, like Adobe Photoshop, would absolutely fly! On a 3 GHz per side dual core, Photoshop performs like it was accessing a 6 GHz single core or even better than that! However, most other software, games, etc. just didn't even recognize the second core and kept plugging along at normal speed.

Fortunately, both Windows XP and Vista can slough off some of their own Operating System functions so that users will notice a serious increase in speed when they go to dual-core, even when running applications that are not "multi-threaded" like Photoshop. One core will be dedicated to only running the application and the other core will run all the background functions.

Therefore the bottom line for most computer users is do not buy another single core. You'll see faster response time and generally have a happier computing experience.

Then what does a quad core do? A quad core is double a dual core. It can process four streams at once. This represents an astounding jump in processing speed for those rare "multi-threaded" applications, but for the majority of regular users, they would be hard pressed to tell the difference between the performance of a dual core vs. a quad core on their desktop, individual core speeds being equal.

So is the quad core CPU being sold just for bragging rights? Not exactly. Even if you are not a current "multi-threaded" application user today, you very likely will be in the future. Programmers are rewriting their applications to take advantage of the multiple cores and you will be left behind if you are still stuck on single core CPUs. Buying a quad core today is a great insurance policy for the future and will ensure that you are pretty well future-proofed against computer obsolescence for a couple of years at least.

AMD and Intel have been engaged in a cutthroat price war so the price of a quad core has fallen sharply, and thus has become very affordable to all.

My best advice to anyone configuring a new system today that they intend to keep for a while is to go with these specifications as an absolute minimum:

Quad-core of minimum 2.66 GHz per core.

2 GB RAM, and make sure you have two more empty RAM slots on your motherboard for future expansion.

500 GB Hard Drive (the prices have come way down).

Don't get suckered into buying a DX10 video card quite yet, unless you're an ardent gamer. These new, expensive and very power-hungry cards offer absolutely no advantage to anyone who doesn't process video at the level of 3D pros, HDTV editors and rabid gameplayers. The video card is an easy upgrade later anyway.

The essence of my advice to all the people considering upgrading from their old single cores is to take the jump directly to quad core. You'll be thankful for it in the future.

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