Power Mac G5s

The long wait for the Power Mac G5s is finally over, and the verdict is in: just as Steve Jobs promised, the next-generation desktops deliver the big performance boost that professional Mac users have hungered for, with growing impatience, for several years.

The new machines take their name from the powerful new processor they’re built around — the IBM PowerPC 970, which Apple classifies as the fifth generation of PowerPC technology (for more details on the new G5s, see “The Next Generation,” September 2003). But the three models that make up the new Power Mac line offer more than just a new CPU: with a brand-new case design, a revamped internal architecture, and a slew of cutting-edge technologies, they represent the biggest makeover for Apple’s pro line since the introduction of the first G4s four years ago.

Great Big Boxes

Visually, the G5s borrow from the design of the popular G4 PowerBooks: instead of shiny plastic, the machines’ elegant exterior is made of brushed aluminum, and the rounded contours of the older models have given way to a more conservative — not to say square — shape.

Unlike with Apple’s laptops, however, no one would call the new desktops compact. Measuring 20.1 inches high, 8.1 inches wide, and 18.7 inches deep, the new models tower over their predecessors.

Despite their size, the G5s have less room for internal expansion than their predecessors: there’s only one empty bay for an extra hard drive, none for a second optical drive to complement the standard SuperDrive, and three PCI (in the 1.6GHz model) or PCI-X (in the two faster models) card slots. In contrast, recent G4s have had bays for three extra hard drives and a second optical drive, plus four PCI slots.

The Sounds of Silence — Almost

So what goes on inside the G5 case? Much of it is occupied by fans (eight of them in the single-CPU models, nine in the dual-CPU version), plastic air deflectors, and giant processor heat sinks — all required to manage the heat generated by the high-powered G5 chip.

A network of temperature sensors and software work together to control the fans, ensuring that they operate only when and where necessary. The beauty of all this elaborate engineering is that it keeps the heat under control without making a racket. In fact, in Macworld’s offices — a fairly typical work environment — we could hardly tell when the 1.6GHz and 1.8GHz models were running. The dual-2GHz model’s noise was more noticeable but hardly oppressive — nothing like that of the infamous “wind-tunnel” G4s.

Of course, the G5s — like any computer this side of the Cube — will be more noticeable in quieter environments, such as many home offices. But considering the power of the G5, Apple’s engineers deserve a tip of the hat for keeping the noise to a minimum this time.

Technology Playland

The G5 processor, with its increased clock speeds and 64-bit capabilities, is definitely the star of the show. But to take full advantage of it, Apple had to develop a whole new set of supporting actors, including a high-speed system controller and a frontside bus that connects the controller to the processor. This bus runs as fast as 1GHz — six times the speed of the equivalent channel in the latest G4s.

Complementing these new data-crunching capabilities are big, fast hard drives: a standard 80GB in the low-end G5, and a 160GB in the other two models, all spinning at 7,200 rpm and supported by 8MB of cache memory. (When it was accessed, the 80GB drive in the 1.6GHz G5 we tested was distinctly noisier than the drive in its higher-capacity siblings, even though both drives were Seagate units with identical acoustical specifications.) The drives are connected to the system via a new industry-standard interface called serial ATA, which offers two big benefits: it can transfer data at 150 MBps, making it 50 percent faster than the Ultra ATA/100 interface in the latest G4s, and it uses tiny, easy-to-connect cables, instead of the big gray ribbon cables and balky power plugs of previous ATA generations. However, no drives on the market can take advantage of the increased speed — this is a technology that hard drives will have to grow into.

With an AGP 8x Pro slot for graphics cards, the G5s also move Apple up a notch in display technology. A speedy Nvidia GeForce FX 5200 Ultra video card is standard in the single-processor models, while the still faster ATI Radeon 9600 Pro comes in the dual-processor model (the model we tested had the $300 ATI Radeon 9800 Pro graphics card). Both cards have two connectors (ADC and DVI, with an adapter that converts DVI to VGA) and can drive two displays simultaneously, in either extended-desktop or mirror mode. Since each connector supports digital resolutions as high as 1,920 by 1,200 pixels (1,600 by 1,200 for analog displays), you can enjoy astounding amounts of screen real estate if you hook up two displays.

It’s hard to think of an up-to-date standard Apple doesn’t support for moving data in and out of the G5s. The 1.8GHz and dual-2GHz models introduce PCI-X technology to the Mac: while the expansion slots in the G4s (and in the 1.6GHz G5) were based on the 33MHz PCI standard, one of the PCI-X slots in the high-end G5s runs at 133MHz and the other two at 100MHz. Although there aren’t yet many PCI-X cards for the Mac, look for video, audio, and storage developers to take advantage of all that extra bandwidth in the coming months.

In addition to the usual 56 Kbps modem and an Ethernet port that handles speeds as high as Gigabit Ethernet (1,000 Mbps), the G5s have internal slots for optional AirPort Extreme and Bluetooth wireless cards. There’s a FireWire 800 port, as well as two of the old FireWire 400 variety (for speed tests on FireWire 800, see ” 250GB FireWire 800 Drives,” Reviews, September 2003). And the three USB ports have been upgraded to USB 2.0, which can handle data as much as 40 times faster than the previous version. (Warning: don’t hook up a USB 2.0 drive, scanner, or printer to the free port on the keyboard that comes with the G5s — though the sleek, white keyboard design is new, the USB hub inside is still limited to USB 1.1 speeds.)

Happily, Apple has finally bowed to popular demand and put some of these ports (FireWire 400 and USB 2.0, plus a headphone jack) on the front panel of the machines — hugely convenient for plugging in a camera or an iPod, especially if the system resides under a desk. Apple has also continued to beef up the Power Macs’ audio capabilities. Besides the headphone jack, the new models have no fewer than four connectors dedicated to audio: analog line-in and -out ports, and optical digital audio-in and -out connectors. Pro audio and video editors will appreciate being able to monitor multichannel audio production and connect directly to digital hardware, such as DAT players, without the need for third-party devices.

By the Numbers

Beyond all the geeky goodies, the real question about the Power Mac G5s was whether they would actually get real work done appreciably faster. Our tests leave no doubt about it: on almost every task we threw at them, the new machines left their predecessors in the dust.

In fact, even the humblest G5 — the 1.6GHz model — outperformed the fastest Mac we’d ever tested before, the discontinued dual-1.42GHz Power Mac G4, on our Speedmark 3.2 benchmark, which measures overall performance in a variety of everyday applications.

Because most of the Speedmark test results don’t benefit from dual processors, the results show only a modest incremental improvement in performance for the dual-CPU G5, compared with the single-processor models. (To view the Speedmark test results, see ” Macworld Lab: First G5 Dual-Processor Test Results.”) But if you look at the results for computation-intensive tasks in media-oriented programs optimized for multiprocessor systems — for example, Adobe Photoshop (with the new G5 plug-in), Maxon’s Cinema 4D, and Apple’s own Compressor utility — you’ll see that the top-of-the-line model delivers another huge speed boost over and above what you get with the single-G5 models. For the customers Apple is targeting with the G5 line, results like these are money in the bank.

Macworld’s Buying Advice

Of the two single-processor G5s, we’d recommend the 1.8GHz model ($2,399) over its 1.6GHz sibling ($1,999). The perfor-mance difference is barely noticeable, but the extra $400 will buy you twice the hard- drive space, twice as much capacity for memory expansion, and PCI-X instead of PCI expansion slots. You might not need those capabilities now, but there’s a good chance you’ll care about them in a year or two.

But for graphics pros, media producers, and anyone else whose productivity is truly limited by processor performance, we recommend saving up for the dual-2GHz Power Mac G5. If your time is money, the performance boost this amazing piece of engineering delivers will pay for itself.

New Power Mac G5 Test Scores

Best results in bold. Reference systems in italics.

Speedmark 3.2 scores are relative to those of a 700MHz eMac which is assigned a score of 100. Photoshop, iMovie, and iTunes scores are in minutes:seconds. Quake scores are in frames per second. We tested the G5 systems with Mac OS X 10.2.7 (G5) and Energy Saver’s Processor Performance set to Highest. The 2GHz DP model we tested had ATI’s 128MB Radeon 9800Pro graphics card installed which is available as a build-to-order option. We tested the baseline systems with Mac OS X 10.2.6. All systems had 512MB of RAM. We set displays to 1,024-by-768-pixel resolution and 24-bit color. We tested MP3 encoding with an audio-CD track that was 9 minutes and 25 seconds long, converting it from the hard drive using iTunes’ Better Quality setting. We tested Quake III at a resolution of 1024 by 768 pixels with Graphics set to High Quality. The Photoshop Suite test is a set of ten scripted tasks using a 50MB file. Photoshop’s memory was set to 100% and History was set to Minimum. For MPEG encoding tests, we encoded a 6 minute, 46 second DV file using the MPEG-2 60 minute-Fast encode preset in Apple’s Compressor application. For more information on Speedmark 3.2, visit www.macworld.com/speedmark Macworld Lab testing by Jim Galbraith.