Friday, June 08, 2001

Introduction

Are all DDR memory-modules created equal? That is one question that we'll be endeavoring to answer during the course of this article.

While competing modules are often more similar in design than not, there has always been a good deal of difference in the fabrication quality of competing vendors. The fact is, its the careful eye for detail and quality control that has long separated premiere memory vendors from the hoards of generic labels that occupy the market.

In fact, it's a pretty well-known fact that memory manufacturers - like most makers of electronic equipment - are in the habit of testing the quality of the components they will use before to assemble them on their circuits. Typically, when a memory chips, or batch of chips, is found not to comply with a company's own internal standards, the offending bits are rejected, placed aside, and often sold-off to enterprises with less exacting standards for use in cheaper, lower-quality products. Often, when consumers buy a stick of memory at their local electronic store without stipulating a brand, it is usually one of these lower-quality, generic modules that makes its way across the counter.

In other words, if you want quality memory for your system, its rather important to ask for a particular manufacturer (Micron, Mushkin, Corsair, etc...) before making a purchase. Otherwise, there is no counting on the quality of your newest trophy.

Often when dealing with the sensitive innards of modern computer systems, the quality of a system's memory can be attributed with the number of blue screens & system crashes that greet users over the course of a day.

The fact is, every electronic device working at the level of radio frequency signals, generally, a signal of 100KHz or greater, has an impedance which should ideally be identical to that of other nearby circuits to which it is connected to. If that isn't the case and that the impedances are not matched, all sorts of instabilities can be created, which can often affect the performance of the entire system. Memory modules aren't immune to this effect, and should be rated for an impedance equal to the memory circuits of the motherboard they'll be installed into.

The problem is, not all motherboards quite meet the impedance standards they were supposedly designed to, and neither do all memory modules. This is where problems begin.

Because of that, and because multiple modules of multiple manufacturers are often installed in the same system, things tend to get a bit messy. It's also quite possible to detect problems with one of a system's memory slots that are not necessarily present in other memory slots.

For all these reasons, its important to be picky about the components one uses to build a system, both in terms of memory, and of the motherboard that will house it.

In short, in the long run of things, it pays for users to spend a little more time and money considering the parts they'll be installing in their computers, and reciting the mantra "You get what you pay for..."

Next: The test setup.