Tips for selecting a memory tester

Exploded view of a typical benchtop memory tester.

Memory testing is a complex task because of the virtually unlimited data combinations that may be stored inside a single device. Fortunately, relatively low-cost memory testers are available that can help simplify the process.

If, however, your company needs to test memory more than a few times each week, you can generally justify a dedicated stand-alone tester based on the time savings alone. This article lists some key features you should look for when selecting a memory tester.

These are critical. A good memory tester uses sockets manufactured specifically for heavy use. The sockets should be rated for at least 10,000 insertion-and-removal cycles. Also, check to see if the socket is soldered to the tester or test head. If it is soldered, the socket could be expensive to replace once it wears out.

To simulate actual operating conditions, test the memory at the true operation speed. Current Windows XP computers are shipping with memory modules operating at 333 MHz or faster. The tester should be capable of running tests at the same or higher frequency.

The common memory format used in desktop computers is 184-pin DDR. Laptop computers typically use 200-pin DDR SO-DIMM modules. What about other formats? You may want to test 168-pin SDRAM, SIMMs, or even chips. Make sure the tester accepts a wide variety of formats.

Can an inexperienced technician use the tester right out of the box, or is there a lengthy learning curve? Ask the memory tester manufacturer for a copy of the manual before purchasing. Scan through the "quick start" section. Tech staff should be able to figure out how to run a diagnostic test on a module within a few minutes, with minimal setup.

Since a lot of information will be displayed during the test, a clear display is essential. Be sure the display is not only backlit, but also large enough to display all of the information clearly. The tester should also include LEDs and clear audio signals during the test cycle. These all provide cues that make testing easier for the technician.

Also, be sure the test log can be viewed after the test has finished. Test logs are important because they allow users to review the module's size, speed, structure, and test results, making it easier for them to pinpoint problems.

Like the rest of the computer industry, memory technology constantly evolves. Does the manufacturer of the memory tester offer frequent updates to the tester's firmware? Can these updates be downloaded via the Internet? How often are they released? The manufacturer of the memory tester should have a proven track record of regular firmware upgrades.

Also, check whether the unit's hardware can be upgraded with new processing capabilities to test faster modules as they are released or if you'll have to purchase an entirely new test system. Think twice before purchasing a tester that will quickly become obsolete.

Does the tester include a software package that allows connection to a PC? Such interfaces offer a superb display, far surpassing the tiny LCD window usually found on the tester. A PC software program is also handy for viewing and printing test logs.

The Serial Presence Detect (SPD) is a tiny serial EEPROM mounted on each stick of memory; the SPD contains size, speed, structure, and other manufacturing data that is vital for the operation of the module. Does the memory tester allow you to view, manage, and edit the small programs used by these SPDs?

You may run across a batch of older modules that you need to identify and test. Check whether a tester is backward-compatible with older memory formats.

A number of memory tester manufacturers have either folded or gone on to other product lines since the technology crash a few years ago. Customers have been stranded with test equipment that is doomed to obsolescence.

It pays to check the company's longevity in the business. Search the Web and Usenet newsgroups for comments others have made about the company's products. Check the company's Web site for announcements regarding future enhancements. Finally, ask around. Check with your business partners and clients. If they work in the computer field, there is a good chance that they own a memory tester.

Memory test equipment will become a necessity in the coming years for the aerospace industry. With flight systems and design requirements growing more complex, continuous checking of each component of the computer system will be vital for flight safety.