Apple said on Friday that it is looking into the problem. More than 650 individuals have signed an online petition demanding that the company address the issue.
According to postings on Apple's online user forum, many PowerBook owners have experienced the problem, which causes white markings to appear on the laptop's screen. By most of these accounts, the spots are less than one inch in diameter. However, some people reported seeing multiple spots on their computers.
Complaints about the problem have been cropping up on several Apple enthusiast sites in recent days.
In response, the Mac maker issued the following statement on Friday: "The new 15-inch PowerBook has been a big hit with customers since its introduction last month. However, some customers are reporting the appearance of faint white spots on their displays after using the system for a short period of time, and Apple is investigating these reports right now. Any customers experiencing this problem should contact AppleCare."
Apple introduced the high-end 15-inch PowerBook in September. At that time, Apple chief executive Steve Jobs said the device "sets the bar for professional notebooks even higher." The computer features a 15.2-inch (diagonal) widescreen display with 1280-by-854-pixel resolution.
Shortly after the notebook computers were released, going by the timing of the user group postings, PowerBook owners began sending messages to Apple's support site, trying to find an explanation for the spots.
Some users reported that they had noticed the distracting flaw immediately upon turning on the new computers, while others said the spots materialised over time. Some PowerBook buyers said they first saw the spots after getting machines back from Apple that had been returned for other repairs.
One explanation of what could be causing the spots was posted to the computer maker's Web site by a self-identified "Apple technician," who claimed to have taken apart his PowerBook to investigate the problem. According to that posting, the notebook incorporates several spacers behind its LCD screen that could be putting pressure on the display and causing the white spots to appear. The posting said the spacers were utilised in the PowerBook's design in order to keep the computer's aluminum casing from bending.
The 15-inch PowerBook G4 comes in two models. One is a 1GHz model that sells for $1,999 (£1,178) and includes 256MB of double data rate (DDR) memory, a 60GB hard drive and a combination drive that can play DVDs and burn CDs. A 1.25GHz version that's priced at $2,599 adds AirPort Extreme plus a backlit keyboard. It comes with 512MB of DDR memory, an 80GB hard drive and a drive that can burn both DVDs and CDs.
