The Need for More than Speed: CPU Tips for PC Buyers

CIO - In the world of digital devices, more - whether it be megapixels or megahertz - was always better. Until it wasn't.

Most of know that digital cameras have gotten so good that we don't need to think about megapixels at all. And all of us PC enthusiasts used to obsess about CPU speed, measured first in megahertz and then gigahertz. But as you may or may not know, the speed of a microprocessor is no longer the best measure of the value you'll get for your money.

Now that Intel, the maker of the majority of CPUs that go into desktop and laptop computers, has recently introduced a new line of chips, this is a good time to brush up on your knowledge of those finger-nail sized dynamos. It's even more important to penetrate the marketing buzz and know what's really going on under the hood if you're about to buy a new computer.

So here's an FAQ that will tell you what you need to know.

Does it matter who makes the CPU in my computer?

The answer to that question changes every couple of years. The two major makers of microprocessors, Intel and AMD, tend to leapfrog each other every few years.

At the moment, Intel's new line of chips, the i3, i5 and i7 (you may have heard them referred to as Sandy Bridge) are clearly superior to AMD's offerings on the higher end. At the low end, AMD offers good value, and if you're looking to save money go with a computer carrying that company's processor. AMD will unveil its own new line of high-end chips in a few months, and the game will continue.

Are Intel's new chips really better than the old, or is this just more marketing hype?

Good question. To get an expert answer, I contacted Dean McCarron, the principal analyst of Mercury Research, who has followed chips and chip design closely for a couple of decades.

"They are," he says. "The new architecture is significantly higher in performance than its predecessor." But you'll note they aren't significantly faster, a paradox I'll explain in a bit.

What's better about them?

They are more efficient, which is to say they get more work done in the same amount of time. Speed in CPU terms is analogous to the ticks of a clock. More speed means that the clock is ticking faster. As the clock ticks, the chip handles instructions, mathematical algorithms that when translated tell the computer what to do. It used to be that the faster the clock ticked, the better off you were.