Newer LCD displays last longer, both on laptops and as a replacement for CRTs on the desktop. "The early laptops with [thin-film transistors] would get dropped pixels. Over the last few years, that has gone away" says Flieger.

Longevity has also improved. "We have LCDs that are 4 years old, and the quality is still much better than a CRT," says Mike Sink, director of infrastructure at Kichler Lighting in Cleveland. Today's LCDs should last six to seven years, according to Lenovo.

Organizations that want to keep systems longer will be more successful if they plan ahead. Yankee Group's DiDio says organizations should buy servers from top-tier manufacturers, select high-end configurations to delay obsolescence and follow best practices such as keeping equipment in climate-controlled rooms.

"We buy a higher-end box. We buy the higher-end versions so you get more bang for the buck," says Fun Sun's Dunham. That strategy also has another benefit: Older servers' functions can be consolidated on the new machines. For example, Dunham replaced five aging servers that performed Domain Name System and system monitoring functions with one dual-processor Xeon server. "It would outperform all five stacked up against it," he says.

After installation, maintenance is critical to system longevity. Heat and dust are the biggest killers of computers, says HP's O'Grady. "Unless you do preventive maintenance, the dust gets inside a PC and causes it to fail over time," he says. Maintenance is especially important where environmental conditions like heat, humidity and dust can't be controlled. "In warehousing and operation environments, the dirt and grime is really bringing these systems down. It just chokes the internals, the heat builds up, and it causes failures," O'Grady says.