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Apple Speeds Up iMacs and Power Mac G4s

During his keynote address at last week's Macworld Expo in New York, Apple CEO Steve Jobs took the wraps off a refresh of Apple's iMac and Power Mac G4 computers. The new systems primarily offer faster performance and further migrate CD- and DVD-authoring capabilities throughout the desktop lines, but make these enhancements with only slight alterations to Apple's price ranges. iMacs start at $1,000 (which is $200 more than the entry-level model at last year's Expo in New York) and high-end G4s still command a minimum of $3,500 - but now buyers get much more bang for their buck.


iMacs -- Pre-Expo rumors suggested that Apple would debut a substantial iMac revision, ditching the bulky CRT display in favor of a sleek flat-panel LCD screen. Such a move would be logical since Apple proudly converted its entire line of external displays to flat panels last May, a move trumpeted by a Macworld Expo banner saying "Hasta la vista, CRT." However, the only external design change Apple made to its iMacs this summer was to eliminate the somewhat off-putting Flower Power and Blue Dalmatian patterned cases in favor of the more-staid Indigo, Snow, and Graphite. Nearly all color has been bleached out of Apple's once candy-colored iMacs.


Under the hood, Apple pumped up processor speeds 100 MHz across the line, so the three iMac configurations now sport 500, 600, and 700 MHz PowerPC G3 processors. The systems also feature 20, 40, or 60 GB internal hard drives (up from 10, 20, and 40 GB respectively), an ATI Rage 128 Ultra graphics processor with 16 MB of VRAM with its own 66 MHz bus (previously only on the most expensive iMacs), and every iMac now sports a slot-loading CD-RW drive which can read and write both data and audio CDs. However, as with Apple's most-recent iMac offerings, no DVD options are available. The $1,000 iMac ships with 128 MB of RAM, while the $1,300 and $1,500 models start at 256 MB of RAM; all have both Mac OS 9 and Mac OS X pre-installed. The new iMacs have only 256K of backside Level 2 cache, but that cache runs at the same speed as the main processor - 500, 600, or 700 MHz - making it pretty effective. The bottom two models are available immediately - the 700 MHz iMac will be available in August.


Otherwise, the iMacs primary features remain largely unchanged: a 100 MHz system bus, a 56 Kbps modem, 10/100Base-T Ethernet, two USB ports, two FireWire ports, two memory expansion slots, optional AirPort wireless networking, and a 15-inch screen with a maximum resolution of 1,024 by 768 pixels. A VGA video output is available, but as before it only mirrors the built-in display rather than expanding the available desktop to an additional monitor.

The new systems are a conservative revision to the iMac line, improving the value-to-dollar ratio and preventing the line from looking underpowered or static in this time of flagging computer sales. Since an LCD-equipped iMac would increase manufacturing costs on a system which already provides a comparatively low profit margin, perhaps it's better for now to stick with a proven design than to replace it with something untried and more expensive. That said, it seems only a matter of time before an LCD screen debuts in the iMac line, especially given Apple's ability to price the new iBooks so aggressively.

Power Mac G4s -- Like the latest iMacs, Apple's changes to the minitower Power Mac G4s are evolutionary rather than revolutionary and don't alter the system's basic price points. The systems sport a new mostly silver case, but otherwise the changes are internal. Processor speeds begin at 733 MHz in the $1,700 model and peak at 867 MHz, with a $3,500 dual-processor 800 MHz system (available in August; the other two are available now) occupying the top pricing spot. The system bus runs at 133 MHz, and the machines have a default 256 MB of RAM (expandable to 1.5 GB). Apple bumped up hard disk sizes (40, 60, and 80 GB drives are now standard) and also made the SuperDrive (which can read and write both CDs and DVDs) available in the mid-range model instead of only in top-of-the-line systems; otherwise, the machines are available with either a CD-RW or a combined CD-RW/DVD-ROM drive. Like their predecessors, the systems support both standard VGA displays and Apple's flat-panel displays (via the proprietary ADC connector, which was analyzed at length in TidBITS Talk). There are three different video systems for the Power Mac G4's 4x AGP slot: a 32 MB GeForce2 MX, the high-end 64 MB GeForce3, or (most interestingly) a 64 MB GeForce2 MX with TwinView, a feature which enables the card to support two monitors with a single combined desktop, so long as one of the monitors is VGA and the other uses Apple's ADC connector. (You can also apparently order standard ATI Radeon cards from Apple, which can be installed in any of the four PCI slots.)


All the Power Mac G4s have 256K of Level 2 cache running at the same speed as the main processor(s), but the two higher-powered systems also feature 2 MB of Level 3 cache per processor running at one-fourth the speed of the main processor. These caches enable the CPU to stash frequently used data and instructions for re-use without having to fetch them repeatedly across the main bus (which runs at a mere 133 MHz). The effectiveness of cache varies widely with the nature of the code being executed at a low level and how well the processor can predict what it's supposed to do next, but tasks like encoding and data transformation procedures - capturing audio or video, compressing a movie, rendering an image, applying a Photoshop filter, etc. - tend to benefit from large, fast caches.

Otherwise, the Power Mac G4s offer now-standard features: four PCI expansion slots, Gigabit Ethernet, two 400 Mbps FireWire ports, two USB ports, optional AirPort wireless networking, three 3.5-inch internal drive expansion bays, and an optional 56 Kbps internal modem, and they ship with both Mac OS 9 and Mac OS X pre-installed.

I'm pleased to see Apple continue shipping multiprocessor systems, particularly at processor speeds which keep up with the rest of the Power Mac line. Although multiprocessor support for Macs is still in its infancy, a handful of Mac OS 9 applications support multiprocessing now, including Adobe Premiere and Photoshop, and the just-shipped Digital Performer 3.0. Mac OS X offers multiprocessing capabilities to Mac OS X-native applications, and as more mainstream programs appear for Mac OS X, I'm hoping the potential power of multiprocessor systems will be realized after years of struggle and fleeting support. (Apple's first multiprocessor system was the 9500/180MP in mid-1996, although former clone-maker DayStar had multiprocessor systems on the market earlier).


Same Price, Only Faster -- Most of Apple's hardware innovation this year has come in the portable space, with the stunning PowerBook G4 Titanium and iBook (Dual USB). So although Apple's latest desktop offerings don't surprise the eye or satisfy rumor-mongers, they ought to be pleasing on the pocketbook: Apple has packed significantly better performance into the same price ranges the company has been charging for new computers so far in 2001. That's fine for now, but the company has made its recent fortunes on design innovation, and the iMac is seeming a little long in the tooth, especially for a machine that redefined the industry when it appeared in 1998. Apple's challenge is to figure out how to redesign the iMac with features such as an LCD screen without losing the tremendous recognition enjoyed by the bulbous iMacs.


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