PowerBook G4

The initial design of the PowerBook G4 was developed by Apple hardware designers Jory Bell, Nick Merz, and Danny Delulis.[4] The ODM Quanta also helped in the design. The new machine was a sharp departure from the black plastic, curvilinear PowerBook G3 models that preceded it. The orientation of the Apple logo on the computer's lid was switched so that it would "read" correctly to onlookers when the computer was in use.[5] PowerBook G3 and prior models presented it right-side-up from the perspective of the computer's owner when the lid was closed. Apple's industrial design team, headed by British designer Jonathan Ive, converged around a minimalist aesthetic—the Titanium G4's design language laid the groundwork for the Aluminum PowerBook G4, the MacBook Pro, the Power Mac G5, the flat-screen iMac, the Xserve, and the Mac mini.

The hinges on the Titanium PowerBook display are notorious for breaking under typical use. Usually the hinge (which is shaped like an L) will break just to the left of where it attaches to the lower case on the right hinge, and just to the right on the left hinge (where the right hinge is on the right side of the computer when the optical drive is facing the user). When the 667 MHz and 800 MHz "DVI" PowerBooks were introduced, Apple changed the hinge design slightly to strengthen it. At least one aftermarket manufacturer began producing sturdier replacement hinges[6] to address this problem, though actually performing the repair is difficult as the display bezel is glued together. In addition some discolouration, bubbling or peeling of paint on the outer bezel occurred, notably around the area where the palm would rest while using the trackpad, and around the rear of the hinges where paint on the back of the machine was often worn off. This appeared on early models but not on later Titanium PowerBooks.

The video cable is routed around the left-side hinge. This will cause the cable to weaken under heavy usage. Many owners have reported display problems such as random lines or a jumbled screen, although few have replaced just the video cable to successfully resolve this problem. There is also a backlight cable that might fail; one option is to replace either or both cables before replacing LCDs.

The aluminum PowerBook G4 was designed by Apple's Vice President of Industrial Design, Jonathan Ive, and used a radically different design from the preceding titanium models. The most obvious change was the use of aluminum, not titanium, to manufacture the body. The keyboard, which was originally black, was changed to match the color of the body. Additionally, the aluminum keyboard was backlit on the 17" model and on one of the 15" models. This was the first case of keyboard internal backlighting seen on a notebook computer. The design was considered superior to most other notebooks when it debuted in 2003, and consequently, it made the PowerBook G4 one of the most desirable notebooks on the market. The external design of Apple's professional laptops continued to remain similar to the aluminum PowerBook G4 until the Spotlight on Notebooks event on October 14, 2008.

Some owners have experienced failure of the lower memory slot on some of the 15" models, with the typical repair being the replacement of the logic board. Apple had started a Repair Extension Program concerning the issue,[9] but it has been noted that some models displaying the issue have not been included. This leaves certain PowerBook G4 owners with only a maximum of 1 GB of RAM to use instead of a full 2 GB.

Apple previously had a Repair Extension Program to fix the "white spot" issue on its 15" PowerBook displays.[10]

There has also been a rash of reports concerning sudden and pervasive sleeping of 1.5 and 1.67 GHz models known as Narcoleptic Aluminum PowerBook Syndrome.[11] Symptoms include the PowerBook suddenly entering sleep mode, regardless of the battery level or whether the PowerBook is plugged in. One cause is the ambient light sensing,[12] and associated instruction set coding, with possible keyboard backlight and sleep light issues accompanying the so-called "narcolepsy". Another cause is the trackpad area heat sensor; system logs report "Power Management received emergency overtemp signal. Going to sleep.".

To correct this, service groups will often replace the logic board or power converter, but the actual fix (depending on the model) for the first cause is to replace or remove the left or right ambient light sensors; and for the second cause, disconnect, remove, or replace the heat sensor, or the entire top case which holds the trackpad heat sensor. Alternatively, there are reports which detail success in removing certain sensor kernel extensions or rebuilding the kernel using the Darwin Open Source project after commenting out the relevant sleepSystem() call; permanent resolution of the sleep issue in this manner is little documented.[13]

The 1.67 GHz model may suffer from manufacturing or design defects in its display. Initial reports pointed to this only being a problem with type M9689 17" PowerBooks introduced in Q2 2005, but then this problem was also seen in displays replaced by Apple Service Providers in this period (e.g. because of the bright spots issue). The devices were the last 17" models shipped with the matte 1440×900 pixel low-resolution display. After many months of usage, the displays may show permanently shining lines of various colors stretching vertically across the LCD. Often this will start with one-pixel-wide vertical lines being "stuck" in an "always-on" mode. Various sites have been set up documenting this issue.[14][15]

On May 20, 2005, Apple recalled 12-inch iBook G4, and 12- and 15-inch PowerBook G4 batteries (model number A1061, first 5 characters HQ441 – HQ507 for the iBook, model # A1079, serial # 3X446 – 3X510 for 12" PowerBook, model # A1078, serial # 3X446 – 3X509.)[16] They were recalled due to short-circuiting which caused overheating and explosion. The batteries were made by LG Chemical, in Taiwan and China. Apple has removed the recall from its website, but it is possible to get a new one by calling them.