Wed, 04 Jan 2006 12-inch PowerBook G4 1.5GHz ; 15-inch PowerBook G4 1.67GHz ; 17-inch PowerBook G4 1.67GHz

In announcing the latest changes to its PowerBook family, Apple highlighted the new models' higher-resolution screens and longer battery life but made no mention of their lower prices.

Indeed, base prices for each of the three models haven't changed. But because the company has amplified the base configurations - with brand-new features and others previously available only at extra cost - the machines are now better value than ever.

Squeeze those pixels
The most noticeable advance in both the flagship 17-inch PowerBook G4 and the popular 15-inch version is higher screen resolution. The 17-inch model (£1,749) now displays 1,680 x 1,050 pixels, up from 1,440 x 900. This offers a 36 per cent increase in the amount of information the screen can show. Put another way, the number of pixels per inch (ppi) has jumped from 101 to 117 - a record high for an Apple display.

In the 15-inch model, which now has one standard configuration priced at £1,399, the default, native resolution has increased to 1,440 x 960 pixels, up from 1,280 x 854 - a 26.4 per cent increase. That comes out to a pixel density of 114 ppi, up from 101 ppi.

All those numbers translate into more room to work and play. It's now easier to keep your palettes alongside the image you're retouching in Photoshop, or your calendar next to your spreadsheet.

There is a downside, though. The only way to add more pixels without increasing the screen's physical size is to make each pixel smaller, and because of the way the Mac currently draws to the screen, all text, graphics, icons, menus, and everything else are correspondingly smaller. As a result, the screen's desktop looks more compressed than on any previous PowerBook. (For comparison, the original Mac had 72 ppi. Today, the 12-inch PowerBooks and iBooks have 106 ppi; the 14-inch iBook has 91 ppi; and Apple's current Cinema Displays range between 98 and 100 ppi.)

To help with readability, Apple has boosted the screen brightness by a noticeable 46 per cent in the 17-inch PowerBook and by 13-15 per cent in the 15-inch model, according to the company. If you do have problems, you can always switch to a lower resolution, but you'll end up with a smaller or slightly less crisp screen display. For a more comfortable view, a better solution would be to zoom your documents in applications that offer that option.

Altogether, I don't think the new default resolutions will present problems for most users. (The only time I found them uncomfortable was when I tried to read the hand-drawn text accompanying some cartoons on the Web.) But if your eyesight is impaired, or if you have any concerns about the new screens, be sure to visit a local retailer to try before you buy.

15-inch: simpler, sleeker
In the previous PowerBook generation, Apple offered two standard 15-inch configurations, one at £1,379 and the other at £1,579. The latter had a 1.67GHz G4 processor and a SuperDrive, while the less expensive configuration had a 1.5GHz G4 processor and a Combo (CD-RW/DVD-ROM) drive. Now there's one standard 15-inch configuration with a 1.67GHz G4 processor and a SuperDrive, priced at £1,399. In effect, that's a substantial price cut, at least for people who want the option of burning DVDs.

That's also true of the new 12-inch PowerBook. The old base configuration, priced at £1,049, had a Combo drive and a 60GB hard drive; you had to spend another £150 to get the version with a SuperDrive and 80GB drive. In the new line-up, the single 12-inch configuration includes the SuperDrive and 80GB hard drive for £1,099. That's a £100 price drop for the top 12-inch model, but the entry-level model has now disappeared.

The latest 15-inch model sports several additional improvements. Although it uses the same graphics chip as its predecessor (the ATI Mobility Radeon 9700), Apple has doubled the video RAM to 128MB and added dual-link DVI support, so the standard configuration can now drive the 30-inch Cinema Display. Previously, that capability was available only as a build-to-order upgrade from the £1,579 configuration.

The updated 15-inch model also incorporates many enhancements that weren't available at all in the previous generation. The 8x SuperDrive, for example, now supports double-layer burning, making it possible to store up to 8.5GB per disc. Standard system memory remains at 512MB, expandable to 2GB, but it's a newer, faster breed: DDR2 (double data rate 2), in place of plain DDR.

The audio-in port can now handle optical/digital audio input as well as line-in connections, while the headphone jack doubles as an optical/digital audio out port. Battery life has improved to a maximum of 5.5 hours per charge, compared with 4.5 hours previously, according to Apple. (Remember, though, that if you're actually using the PowerBook, a charge won't last nearly that long. Apple claims that the battery life is 3 hours and 45 minutes for a combination of wireless web browsing and editing a text document, but only 2 hours and 15 minutes for DVD playback.) 17-inch: less room for improvement

Even before this update, the standard configuration of the 17-inch PowerBook had a 1.67GHz G4 processor, a SuperDrive, 128MB of video RAM, dual-link DVI, and optical/digital audio in and out ports. That doesn't leave a lot of possibilities for upgrading, especially since the 1.67GHz remains the fastest G4 available. But Apple has added three improvements it also made to the 15-inch model: DDR2 memory, double-layer support in the SuperDrive, and an increase in battery life to a maximum of 5.5 hours. Finally, hard-drive capacity has increased from 100GB to 120GB, as high as you can currently get in a notebook.