TECH TIPS
Faulty memory chips can plague PCs
Gannett News Service
Microsoft's Bill Gates once said that personal computers would never need more than 640 kilobytes of operating memory, known as RAM. But time flies, and today's PC's require 200 times that amount, or about 128 megabytes, to run state-of-the-art operating systems such as Microsoft's Windows XP or Apple's Mac OS X.
So it's not unusual for PC users to stuff their computers full of memory chips. Though prices have risen in recent months, computer memory is still relatively inexpensive.
In most cases, the memory upgrade process goes smoothly. But problems sometimes occur because of defective memory chips. However, bad RAM is often tricky, if not impossible, to diagnose.
"Sometimes you'll get random errors that don't make sense," said Dave Fuschino, a service guru at Data Doctors, an Arizona-based chain of PC repair shops.
So what do you look for?
"If your system has worked well, you install memory and suddenly you have problems with applications working properly, or frequent system crashes, it might indicate a problem with RAM," said Brandon Guthrie, senior technical analyst for Crucial Technology, the memory division of Micron in Boise, Idaho, which supplies RAM for computer makers, including Apple and Dell.
A simple way to check is to remove the RAM upgrade and see if the PC runs normally again. If it does, contact a dealer and arrange to replace the memory.
Fuschino advised: "Don't buy the cheapest thing you can find. You can run into all sorts of problems that way. Look for a lifetime warranty. Stay away from RAM with a 90-day or one-year warranty. You may pay a little more, but you'll know you're getting top-quality memory."
Buying the right memory module for a PC isn't easy. RAM modules may look the same, but they differ in technical specifications. Installing the wrong type of memory can result in poor performance or even damage a PC's delicate electronics.
Guthrie said buyers should examine the label on the box or the sticker to make sure they have purchased the right product. If they're not sure, they should ask the dealer because once they've installed the memory and turned on the PC, it may be too late because the damage already will be done.
Although installing RAM on an Apple Macintosh or Windows PC is usually fairly easy, it's important to take precautions. First, turn off the PC and then touch a metal part of the case to discharge static electricity. Some memory vendors include a wrist strap to drain static electricity.
Next, insert the RAM upgrade gently into the appropriate slot. Make sure the pins on the memory module line up properly and don't force the chip into position. This can damage the plastic slot or the little clips that hold the memory in place, and repair usually involves replacing the PC's main circuit board.
Sometimes memory problems are subtle, and system problems increase only slightly. Running a program that identifies bad memory can help diagnose PC instability.
Guthrie said two free test tools for Windows PCs work well — Memtest86 and DocMemory. Each program runs in DOS or command line mode and takes roughly 15 minutes to check a PC's memory.
New Macintosh computers from Apple include an Apple Hardware Test CD that can also check for bad memory and other hardware problems, but the tests are relatively brief and not thorough.
Apple's authorized service providers use an application called Mac Test Pro, which can run component tests for hours to better detect a hardware issue. A commercial diagnostic application, TechTool Pro, from MicroMat ($98) can also perform extended memory tests.
Guthrie said computer users who don't want to go through the bother of trying to perform a self-diagnosis, should ask a dealer or service center to test the memory, though a fee sometimes applies.
