Mahatma Gandhi, Martha Graham, and Pablo Picasso might not have chosen to peddle computers if they were alive, but they are doing a pretty good job from the grave with Apple's new line of G3 Macs. Starting at $2,000, these high-speed Macs were largely responsible for Apple's unexpected return to profitability last quarter (which certainly seems like different thinking for Apple). But the G3 systems probably would have done OK even without Picasso's help.

Thankfully, you no longer need the Rosetta stone to figure out which Mac suits you best. Instead of having to decipher myriad cryptic Mac model numbers, you simply choose from three G3 Macs: a build-to-order desktop Power Mac G3, a build-to-order minitower Power Mac G3, and a high-end PowerBook G3 laptop. The G3 Macs are more affordable than earlier Power Macs, but you don't need to buy a new system to catch G3 fever. G3 processor upgrades are now available for every old Power Mac and Power Computing and Umax clones.

Of the three G3 models, Apple sent me the PowerBook G3 to evaluate. Laptops are usually the slow-witted cousins of any computer family, but this isn't the case with the PowerBook G3. Although its 50MHz system bus is slower than the 66MHz bus in the desktop models, the PowerBook G3 uses the same PowerPC processor as the desktop systems, not a lobotomized, low-power version.

I also tested Newer Technology's MAXpowr G3 upgrade card, which I installed in a Power Mac 7500. The G3-powered Power Mac 7500 wasn't quite as fast as the PowerBook G3, but it was in the same league. And while G3 speed doesn't come cheap, prices are coming down. A MAXpowr G3 upgrade starts at $499 for a Power Mac 6100. The MAXpowr G3 upgrade I tested, a 250MHz model for a Power Mac 7500, costs $949.

A Faster Generation

G3 is Apple's name for the third generation of PowerPC processors, which Motorola and IBM dubbed the PowerPC 750. These aren't your father's PowerPC chips. While the clock speeds of the G3 processors are slower than those of the top PowerPC 604e processors, the G3s are the faster chips. For instance, a 266MHz G3 outperforms a 350MHz PowerPC 604e.

There are several reasons for this speed boost. The first is IBM's manufacturing process, which packs transistors closer together. This makes the processor smaller, and smaller means both faster (because the electrical signals must travel shorter distances) and cheaper (because the chips consist of smaller amounts of costly materials).

Smaller processors also use less power. Because the G3 chip consumes only 5.7 watts, it can be used in the PowerBook G3 without modification. This isn't the case with other, power-hungry desktop processors. For example, before the Pentium II can be dropped into a portable, Intel must wean it from its 40-watt diet, which will require removing transistors and, consequently, computing power.

Another reason for the G3's high performance is a new kind of CPU cache called backside cache. In previous Power Macs, the Level 2 cache is located on the motherboard and communicates with the processor through the system bus, which runs anywhere from 40MHz to 66MHz. In the G3 Macs, the cache is located right on the processor card and communicates with the processor via a dedicated bus, which can run as fast as half the processor's clock speed. This means, for example, that a 266MHz G3 can communicate with the cache at 133MHz.

Apple is finally offering build-to-order systems, but the options pale in comparison to those of the custom-built PCs offered by the likes of Dell, Gateway 2000, and local PC systems vendors. When you buy a Power Macintosh G3 desktop system from a retailer or directly through Apple's Web site, you can choose between a 233MHz or 266MHz G3 processor with 512K of backside cache, from 32MB to 192MB of RAM, between a 4GB or 6GB IDE hard disk, and from 2MB to 6MB of video RAM. And you can add an internal Zip drive or a K56flex 56Kbps modem.

The G3 minitower offers a few more options. You can stuff it with up to 384MB of RAM, replace the standard 64-bit video adapter with a 128-bit model with 8MB of video RAM, and add 24-bit video input and output. And instead of an ordinary 4GB or 6GB IDE hard drive, you can choose a 4GB or 9GB high-performance SCSI drive. However, choosing the faster SCSI drive means also footing the bill for a PCI-based Ultra Wide SCSI adapter, because the SCSI-2 bus built into the G3 Macs is a slower brand of SCSI.

The Power Mac G3 systems are the fastest Macs ever. But in spite of their 3D graphics accelerators and other impressive features, the Power Mac G3s are really mid-level machines. They use cheap, slow IDE hard drives and lack the expandability of high-end systems like the Power Mac 8600 and 9600. For instance, the G3 machines can support up to 192MB or 384MB of RAM, but they have only three DIMM slots, so you must fill them with high-capacity DIMMs. A high-end Power Mac G3 with more empty RAM slots, drive bays, and PCI expansion slots, and possibly a faster SCSI bus, will be released in a few months. The system will probably come in a tower configuration based on the Power Mac 9600.

PowerBook G3

The PowerBook G3 comes with a 250MHz G3 processor, but runs slower than the 233MHz desktop G3 because its system bus and backside cache are slower. The PowerBook's system bus runs at 50MHz, while its 512K of backside cache communicates with the processor at 100MHz. Nevertheless, unlike the desktop G3s, the $5,700 PowerBook G3 is truly a high-end machine, usurping the title of luxury laptop from the PowerBook 3400c.

The PowerBook G3 uses the same case and crisp, 12.1-inch, active-matrix display as the PowerBook 3400c. And like its predecessor, the PowerBook G3 has a built-in modem/Ethernet port, a connector for an external VGA monitor, and PC Card slots for two Type II cards or one Type III card. It lets you swap the floppy and CD-ROM drives without restarting, and even weighs the same as last year's PowerBook, 7.5 pounds with the floppy drive installed.

But the PowerBook G3 isn't just a PowerBook 3400c with a new processor and backside cache. The G3's 50MHz system bus is faster than the 3400c's 40MHz bus. Its display gets a speed boost from a faster video controller and 2MB of video RAM. Its 5GB hard disk is bigger than the 3400c's 3GB drive, and its standard RAM has been doubled to 32MB (expandable to 160MB).

A side benefit of the G3's low power requirements is longer battery life, which is boosted by a new lithium-ion battery. I found Apple's claim of two to four hours of battery life to be accurate, since I once completed two two-hour work sessions on one battery charge. As with the PowerBook 3400c, however, frequent use of the G3's CD-ROM drive will drain the battery fast.

Apple also claims that the PowerBook G3 is twice as fast as the 240MHz PowerBook 3400c/240. My real-world tests seem to confirm this. As you can see from the chart of results on page 113, the PowerBook G3 averaged more than twice the speed of the 200MHz PowerBook 3400c/200 I tested last summer.

Moreover, the PowerBook G3 runs processor-intensive tasks, such as the Excel spreadsheet recalculation, at triple the speed of the PowerBook 3400c/200. (To read my May 20, 1997, review of the PowerBook 3400c/200, see "Go Apple, Go" at www.currents.net/magazine/national/1510/crem1510.html.)

G3 in Old Macs

With a Newer Technology MAXpowr Pro G3 processor upgrade card installed, my old Power Mac 7500 ran nearly as fast as the PowerBook G3, averaging about 15 percent slower in completing the same set of tasks. Like the PowerBook, the upgrade card had a 250MHz G3 processor and 512K of backside cache, but the Power Mac 7500 has a slower system bus than the PowerBook G3. However, Newer's 250MHz G3 upgrade card outgunned its 225MHz MAXpowr 604e processor card by about 20 percent on average.

(In the same set of tests, the 225MHz MAXpowr 604e upgrade proved to be about twice as fast as the Power Mac 7500's original 100MHz PowerPC 601 chip. See "Turbocharge Your Mac" at www.currents.net/magazine/national/1521/crem1521.html.)

With the MAXpowr Pro G3 installed, the Power Mac 7500 ran not only faster but also quieter than it does with the 604e processor card. That's because the 7500, like many other Power Macs, has a variable speed cooling fan. When the inside of the Mac gets hotter, the fan speeds up and makes more noise. Because the G3 chip puts out much less heat than the 604e, the Mac's fan doesn't have to work as hard.

Newer Technology is just one of many companies now offering G3 upgrade cards for older Power Macs, including the first generation Power Macintosh 6100, 7100, and 8100. Unlike later Power Macs, these models were not designed to be upgradeable; their processors aren't located on a removable daughter card, but soldered to the motherboard. The G3 upgrade cards for these Macs fit into their Processor Direct Slot (PDS). For Macs that have a DOS Compatibility Card or AV video card already installed in the PDS slot, the MAXpowr G3 card comes with a clever pass-through connector that lets both the G3 card and the older card share the slot. Ranging from $499 to $799, the MAXpowr G3 upgrades for the 6100, 7100, and 8100 are available with 1MB of backside cache and a faster cache bus than Apple's Power Mac G3 systems, running at two-thirds the processor's clock rate.

Finally, owners of Power Computing and Umax clones aren't left out of the G3 party, either. Newer offers processor cards for those Macs as well.

It's a G3 World

I expect Apple to quickly replace its PowerPC 603e- and 604e-based product lines with G3 systems, not only because of the raw speed advantage, but also because the new models employ a cost-cutting, just-in-time manufacturing process that helped Apple reduce inventories and earn its recent profit.

But the current G3 systems are just the start. We'll soon see at least one high-end G3 system aimed at graphics and multimedia pros. I also predict that some lower-end, G3-based desktops and PowerBooks will make up part of Apple's new product lineup next fall. With the G3 chip available in both high-end and low-end systems, and in upgrades for formerly obsolete systems, this is one technical innovation that raises every Mac user's boat.

© 1998 John Rizzo. All rights reserved.

John Rizzo is a computer journalist and the author of several books, including "How Macs Work" by Ziff-Davis Press, and the creator and Webmaster of MacWindows (www.macwindows.com), the Web site for Macintosh-Windows Integration solutions. You can reach him at zmac1@aol.com

Feature This: G3 Configurations  Power Macintosh G3Power Macintosh G3Power Macintosh G3PowerBook G3 Configurationdesktop modeldesktop modelminitowerlaptop Processor speed233MHz266MHz266MHz250MHz Backside cache speed117MHz133MHz133MHz100MHz Backside cache size512K512K512K512K System bus speed66MHz66MHz66MHz50MHz Min./max. RAM32MB/192MB32MB/192MB32MB/384MB32MB/160MB Min./max. video RAM2MB/6MB2MB/6MB2MB/6MB2MB Min./max. hard disk4MB/9GB4MB/9GB6GB/9GB5GB CD-ROM drive24x24x24x20x Internal ZIP drive **  Networking10Base-T Ethernet10Base-T10Base-T10Base-T/33.6 modem Empty drive bays211none Expansion slots3 PCI3 PCI3 PCI2 PC Card Memory slots3 DIMMs3 DIMMs3 DIMMs1 module Starting list price$1,999$2,399$2,924$5,699

Where to Buy

Power Macintosh G3
PowerBook G3
Apple Computer
800/795-1000
www.apple.com

MAXpowr Pro G3 Processor Upgrade
Newer Technology
800/678-3726
www.newertech.com
List price: $499 to $2,245, depending on speed (210MHz to 275MHz), cache size (512K or 1MB), and computer model