Nearly one-fifth of all notebook PCs will break down over their lifetime, needing a new hardware component to fix the failure, a study reveals.

The broken part could be as simple as a laptop latch, but the most frequent failures are motherboards and hard drives, according to a study released Monday by Gartner.

Desktops suffer from the same weakness, but they break less often. Five per cent of desktop PCs purchased in 2005-2006 will break within the first year, and 12 per cent will break within four years, Gartner estimated.

In comparison, 15 per cent of laptops will break within a year, and 22 per cent will break within four years.

Screen design improves

In recent years, broken screens were the most common laptop failures, but that has changed, said Leslie Fiering, research vice president at Gartner.

Notebook manufacturers have improved their designs, reducing screen breakage by adding structural rigidity to the notebook casing and screen bezel, and providing more clearance between the screen and keyboard when the lid is closed, she said.

At the same time, motherboards have grown more complex. IT managers used to replace single parts like a NIC (network interface card) or modem, but today those parts are integrated onto the motherboard, so managers must replace the entire motherboard to fix a single component.

After motherboards and hard drives, the next most common notebook hardware failures are latches and hinges on the chassis, and lost keycaps and spilled drinks on the keyboard.

Slow progress

PC vendors are making progress in building more reliable machines, Fiering said. Just two years ago, new desktops would break 7 to 15 per cent of the time, and laptops would break 20 to 28 per cent of the time.

Vendors have improved those numbers by testing more components, increasing penalties to suppliers for broken parts and scanning PCs during repairs to prevent future problems.

This study was difficult to research because most vendors refuse to discuss reliability with analysts, Gartner said.

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