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PowerBook G4 15" (FireWire 800): More on white spots on screen

PowerBook G4 15" (FireWire 800): More on white spots on screen

Yesterday and Tuesday we covered a significant number of reports of "white spots" or "pools" on the screens of new PowerBook G4 15" (FireWire 800) laptops. Since posting more details on the issue yesterday, we have received a large number of confirmations of the problem from readers. More significantly, after posting a 15" Desktop picture that "maps" out five such spots on one user's screen, the overwhelming majority of users who have contacted us confirm that although they may have anywhere from one to all of the spots shown in the picture, and the spots may vary in size relative to those shown, the locations of the spots match up perfectly.

Although we have received a few reports of screens that showed these spots right out of the box, in the vast majority of cases the screen looked fine at first, but gradually developed the spots over a period of a few days to a few weeks.

In addition to the feedback we have received directly from users, a number of other sites, forums, and mailing lists around the Web have been airing similar concerns. Apple's Discussion Forums have also been getting significant traffic over this issue (example threads: main, 2, 3, 4, 5, 6, 7, 8).

Casting doubt on the theory that the spotty laptops may have come from a limited production run is the variance in "demographics" across the problematic units. Spots have been reported on both stock and build-to-order units. They have been reported by users who received their laptops on the first day they were available, as well as by people who have received theirs just few days ago. They have been reported by users in Hong Kong, Australia, Boston, Southern California, and many other locations. Sources include local retailers and Apple Stores, mail order vendors, and the Apple Store Online. These varying dates, locations, and sources would seem to rule out any geographic or production concentration. Finally, users who have had their entire laptop replaced (not just repaired) report that the problem often appears on the replacement after a short period of time. (One user, whose pictures we linked to, purchased a unit in New Jersey in September, and later had it replaced in Malaysia -- both units had the same issue.)

Causes? In our initial report, we posted the comments of a reader who felt the spots were due to heat from the bottom of the laptop ("hot spots" on the keyboard). However, MacFixIt reader Carter Jernigan reported that he has seen this problem on two different 15" PowerBook which were used only at a desk, without ever being closed. We have received similar reports from other readers, which would seem to eliminate heat from the CPU/hard drive as a possible cause.

On the other hand, yesterday we posted remarks from a user who felt certain that the cause was not heat, but rather pressure on the screen. Many of the comments we have since received seem to support that theory. One MacFixIt reader pointed out that "if you take your finger and drag it firm, but lightly across the center of the back of the screen, you will get ripples in the white spot areas." An Authorized Apple Reseller commented that some of the new 15" PowerBooks have "obvious external distortion on the back of the lid." Another reader postulated that perhaps the PowerBook's keyboard isn't entirely flat, and that "bumps" in the keyboard are pressing on the front of the display, causing the spots to form.

Finally, it should be noted that although the vast majority of reports of this issue come from owners of the new 15" PowerBook G4, we've received a few individual reports of similar screen problems on older models, such as the 12" PowerBook G4, iBook 800MHz, iBook 600MHz (both 12" and 14"), PowerBook G3 (Pismo), and a few different versions of the PowerBook G4 Titanium (including a number of instances from one reseller). However, one thing that sets these reports apart from the issues with the new 15" PowerBook G4 is that in these reports, the problem took much longer to appear -- after a period of months, or even years. To add to that, reader Steven Joniak reports seeing similar "spots" on IBM, Dell, and Toshiba laptops, and that "the spots show up in about the same areas"; Garth Gillespie reports seeing the same kind of problem on an LCD monitor used for trade shows that got its share of physical abuse; and Jerry Jividen has a similar problem on his 22" Apple Cinema Display. So it appears that this problem is not necessarily isolated to the new 15" PowerBook, but is instead a potential problem with LCD displays in general.

So why is the problem so common in the new 15" PowerBook, and why does it happen so quickly? Although we can't say with certainty, if you put these factors together -- that the cause is most likely pressure, that "spotting" seems to occur on LCD displays in general when under stress, that the screen on the Aluminum 15" PowerBook appears to be more flexible than the screen on the Titanium 15" model -- a believable conclusion is that the screen casing on the new 15" PowerBook is less rigid or otherwise less protective than that of the previous generation of 15" PowerBooks, and that something, either in the screen enclosure itself or from the bottom of the laptop, is putting pressure on the screen.

Reader David Kirkpatrick put it this way: "The white blotch problem is therefore not due to technology specific to this generation of Powerbooks, but must be inherent in the LCD screen assembly itself. The frequency at which this problem is showing up, compared to previous PBs, indicates that some alteration in the way that the screen is assembled has led to the problem. Hopefully Apple will identify the specific cause and correct the design."

Apparently supporting this theory, we received a detailed report from an Apple Authorized Reseller who has seen the problem on a large number of units. He has seen it on a few older 15" Titanium PowerBooks when the screen is stressed continually, but also on the newer units with very little screen stress. His theory is that the issue is related to a combination of poor lid design and poor handling. He provided a number of specific examples of laptop user "abuse" that resulted in pressure being placed on specific points on the screen; "white blotches" at those points were the result. His conclusion is that a stronger and more protective lid design might have prevented this problem from being so prevalent.

Apple Response? We haven't received any word yet from Apple on this issue. However, a good number of readers report that Apple has replaced their PowerBooks due to these spots, indicating that Apple is aware of the problem. In fact, two MacFixIt readers provided us with information about "internal" Apple Knowledge Base articles that were allegedly available to the public -- unintentionally -- a few weeks ago. Although we cannot verify their authenticity, one of the articles we were forwarded mentioned that "PowerBook G4 (15-inch FW 800) computers are being captured if the display pools or has white spots." Unfortunately, as of today, it appears that even if Apple does replace your PowerBook, the replacement units often have the same problem, as mentioned above.

On a positive note, MacFixIt reader David King contacted Apple about his PowerBook and was told that Apple was aware of the problem and is working on a solution. They gave him the option of getting a replacement screen now, or waiting until the "real" fix is ready. At this point, given that so many replacement units are exhibiting the same problem, perhaps waiting for such a fix is a better option; however, if your PowerBook "has spots," be sure to contact Apple anyway in order to document your case and get a case number.

Are you seeing spots? Drop us an email at

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