How to Buy a Used Computer

While there are rules to follow when searching for the perfect “previously owned” computer, in the end, the buyer of a used computer--much like the buyer of a used car--is operating as much on instinct as cold, hard facts.

And it may be even more difficult for the computer buyer than the car buyer, because these high-tech wonders don’t come equipped with odometers, tire treads and other telltale indicators of how much or how hard a machine has been run.

Nevertheless, the potential bargains of a used computer are alluring. And if this is what you want, follow the tips from the National Assn. of Computer Dealers listed below, and then remember: unless you get a warranty, it’s still buyer beware.

1. Do your homework. Among the best sources of information are the classified ad sections of newspapers and computer magazines and services listing prices commanded by used machines. Compare these used prices to new prices, particularly those offered at special sales. In some cases, you might do almost as well buying a new machine on sale than buying a used one. New high-tech equipment loses 25% to 50% of its retail value within three months of its initial purchase.

2. Before making your purchase, work with the machine. It takes a minimum of an hour for heat-related problems in the system to manifest themselves, so allow at least that much time for your test run.

Your test should include several steps. If you’re buying an IBM personal computer, or one of its many clones, run one or more of the built-in diagnostic test programs contained in the machine’s own operating system. There are software programs available in computer stores to test the internal workings of an Apple computer.

Check the screws on the back of machine. If they look well worn, it could signal that the owner has opened the box many times. The openings may have been to add new function boards or they could indicate that the machine has been repeatedly repaired. 3. Ask the seller to give you as much of the original purchase material as he has, including the machine’s original operating manuals. You should also check to see if the original warranty is still in effect. If it is, it often can be transferred to a new owner.

4. Take your time. Don’t allow yourself to be rushed into making a decision. Unless you have some sort of money-back guarantee or warranty on defects--which is not usual in used equipment transactions--the machine you buy is the machine you get.