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Apple iMac Core Duo review: Apple iMac Core Duo

We knew Apple and Intel were getting hitched, we just didn't expect it would be this soon. The changes are mostly under the hood, but for the moment, you should proceed with caution if there's a particular non-Apple-made program you're fond of. The new Intel chip in the iMac Core Duo is fast with software that's been programmed for it, but for nonnative apps, the going is slow.

Rich Brown Former Senior Editorial Director - Home and Wellness
Rich was the editorial lead for CNET's Home and Wellness sections, based in Louisville, Kentucky. Before moving to Louisville in 2013, Rich ran CNET's desktop computer review section for 10 years in New York City. He has worked as a tech journalist since 1994, covering everything from 3D printing to Z-Wave smart locks.
Expertise Smart home, Windows PCs, cooking (sometimes), woodworking tools (getting there...)
Rich Brown
9 min read
Apple iMac Core Duo (2.0GHz, 20-inch)

The iMac Core Duo is Apple's first desktop computer to result from the company's partnership with Intel. Combining Intel's new 945GM mobile chipset and the Intel Core Duo processor, the Apple iMac Core Duo marks a significant change for the iconoclastic company, bringing it closer in line with the "Wintel" world. (Boot Camp brings it a couple of steps closer.) More than a perception shift, however, the move to Intel's Core Duo technology allows Apple to keep up with the performance and capabilities of its Windows-based competition. The iMac's biggest trouble is that it's experiencing some of the growing pains inherent to new technologies, but the recent addition of Windows XP-enabling Boot Camp makes up for a lot of lost ground.


Apple iMac Core Duo

The Good

Fast native application performance with Mac OS X; can run Windows via Boot Camp; same core features as the Editors' Choice-winning iMac G5 for the same price; updated iLife '06 digital media software included; faster 3D graphics and memory than the iMac G5; major software vendors have all committed to port over their software to the Intel platform.

The Bad

Nonnative software runs slowly on Mac OS.

The Bottom Line

Apple's Intel-based iMac Core Duo boasts an enviable combination of a first-rate design, an impeccable software bundle, and the newfound ability to run Windows in addition to Mac OS X. You simply won't find a more feature-packed, versatile mainstream computer.

Not every software vendor has completed the necessary reprogramming to ensure full performance on the new iMacs, so some applications, Photoshop among them, run significantly slower than on even the older iMac G5s. Fortunately, it's only a matter of time until the software catches up (most major vendors have committed to the transition). And because the new iMac retains and expands on the features of the older models without a price increase (our 2.0GHz, 20-inch review unit costs $1,799 with 1GB of memory; the 1.83GHz, 17-inch model starts at $1,299), the news on this one is mostly good. We do recommend looking into your favorite apps--especially if you use them for work--to see how the compatibility is shaping up before making a purchase. Just want to muck around with iLife and other Apple apps? Then there's no reason to wait.

Software compatibility issues aside, the move to Intel chips is significant to the iMac for reasons beyond the speed increase. First, as its name implies, the Intel Core Duo chip is a dual-core CPU. Not only will you get better multitasking performance, you'll also receive a boost from applications that are multithreaded, or designed to take advantage of two processing cores. This means more efficient, faster computing overall. But beyond the CPU, the Intel 945GM chipset itself introduces some significant new technologies to the iMac Core Duo. The motherboard supports faster 667MHz DDR2 SDRAM, which results in faster access times between the memory and the CPU than with the iMac G5 and its 400MHz DDR memory. As with the iMac G5, the baseline iMac Core Duo ships with a respectable 512MB of memory, but you can add up to 2GB more for an additional $300 at checkout. The stand has RAM-installation instructions printed on the bottom, but bear in mind that opening the case for DIY upgrades is difficult and will probably result in scrapes and scratches.

The iMac Core Duo also has more-advanced 3D graphics capabilities. Apple has upgraded the iMac to ATI's Radeon X1600 3D chip (the 128MB version is standard; 256MB will run you $75 more), which supports all the latest 3D techniques. No one would ever recommend that you buy an Apple computer if gaming is your primary objective, but it's nice to know that if you want to play the occasional game, the iMac Core Duo should be able to keep up, as long as you keep your image quality and performance expectations reasonable.

Along with the core hardware change, the iMac Core Duo is a remarkably complete midrange desktop PC. It boasts the same features as its predecessor, such as an integrated iSight camera and iChat software for videoconferencing and a remote control and the intuitive Front Row suite for playing your digital media files. Both iChat and Front Row have been reprogrammed to run on the Intel chips, as has Apple's Tiger OS X 10.4.4 and the newly announced iLife '06 digital media productivity software, which Apple includes in all new iMacs for free. We're also happy to report that the bundled wireless networking and Bluetooth adapters are also still part of the iMac package, letting you retain the iMac Core Duo's uncluttered aesthetic on your desk.

As we've said, though, the native software support is the crux of the issue for the iMac Core Duo. Thanks to Apple's transparent Rosetta technology, you can run all Apple software on the new iMac. The question is, how fast? As our benchmarks show, the performance difference between software that has been ported to Intel systems, such as iTunes, and those apps that have not been ported, such as Adobe Photoshop and Sorensen Squeeze, is remarkable. But Rosetta is required only when running the Mac OS; with Boot Camp, you can turn the iMac Core Duo (and the other Intel-based Macs) into a dual-boot machine that runs full versions of Mac OS X and Windows XP.

We installed Boot Camp on the iMac and saw nonnative apps, such as Photoshop, run much faster in the Windows environment. We expect this performance delta to shrink or disappear all together once more universal binary apps--nonnative Mac software built for the Intel platform--are released. Still, the transition is far from complete. Though Apple can boast of the hundreds of apps that do run natively on Intel-based Macs, Adobe's universal binary version of its next Creative Suite, which includes Photoshop, is likely more than a year away. Do note, however, that if you are frustrated by Photoshop performance on an iMac currently, you'll need to purchase the Windows version in order to do an end run around Rosetta and operate within Windows. You'll also need to pick up a copy of XP Home or Pro.

On our iTunes test, the iMac Core Duo running Mac OS X was 30 seconds faster than the 2.1GHz iMac G5 at encoding MP3 files. That doesn't translate to the two-to-three times boost Apple CEO Steve Jobs claimed at the iMac Core Duo's introduction; it's more like a third faster (35 percent, actually). Similarly, the iMac Core Duo showed an improvement on our Doom 3 test, posting 16.2 frames per second at 1,024x768, compared to the iMac G5's 11.6. That's not a significant increase, nor is it even a playable frame rate, but please note that Doom 3 is a nonnative application (although a native version has been released since we originally ran this test). Instead, the nonnative speed increase is likely due to the vast leap forward in 3D graphics technology on the iMac Core Duo. And if ATI's newer 3D chip can help Doom 3 running nonnatively, we think it's reasonable to expect that if a native version emerges, you might see an even larger performance gain. Running the iMac Core Duo again in Windows didn't do much to change the picture; our iTunes test took 14 second longer to complete, and Doom 3 frame rates increased but not to a point where you'd call it playable.

Photoshop paints a different picture entirely. First, when in Mac OS X, iMac Core Duo was 81 percent slower than the iMac G5, taking 6 minutes, 30 seconds to run our photo script compared to the iMac G5's 3-minute, 36-second time. Then in Windows, the iMac completed the test in 2 minutes, 49 seconds--less than half the time it took the same system when running the Mac OS X and using Rosetta.

The story continues with another nonnative app, the video-encoding application Sorenson Squeeze 4. In Mac OS X, Rosetta really takes its toll, to the tune of an abominable 24 minute score on CNET Labs' benchmark. Switching to Windows, the score drastically improves to 4 minutes, 16 seconds.

Looking at the iMac Core Duo's performance under Windows against other Windows PCs shows no real surprises. For example, the iMac Core Duo's performance fell right between two recent, midrange, multimedia-friendly Viiv PCs from Dell and HP on both our SysMark 2004 Windows application benchmark and our Sorenson Squeeze video-encoding test.

There has also been some talk online about iMac Core Duo being able to boot faster than the old iMac G5. A video posted on Web site YouTube showed the iMac Core Duo booting faster. Then Apple enthusiast site Silver Mac posted test results showing that the iMac G5 was actually not as bad. Curious, we ran our own boot-time test, comparing this iMac Core Duo to the 2.1GHz iMac G5. Each system started from its fresh-from-the-box disk image, then we updated all of the default software via Apple's autoupdate tools. Under those conditions, we ran three clean boots and stopped the clock when every component finished loading. The iMac G5 booted in an average of 46.6 seconds. The iMac Core Duo came up in an impressive 25.7 seconds. Your mileage may vary based upon a number different configurations and installed software, but conditions being as equal as they can be given different chipset and operating systems, the iMac Core Duo has a clear edge in this regard.

But back to core performance. If you find those nonnative scores in Mac OS X alarming, you're not alone. You can take heart in the fact that some third-party programs--Quark, for example--have already been ported over to the so-called universal binary that will run on both Intel-powered and older PowerPC-based Macs. Canon, Epson, and HP have all also announced that full universal binary drivers for their Apple peripherals will come with the iMac Core Duo as part of OS X 10.4.4. Photoshop maker Adobe and other major software vendors have committed to updating all of their Mac products. And in fairness, the iMac Core Duo came out six months earlier than its software partners expected. Whether they're able to complete the updating process before a new iMac comes out we can't say. Until then, you can always download Boot Camp and buy a copy of Windows, along with any Windows apps that are near and dear to you.

Apple has improved the iMac's specs and features, but it still hasn't come through with that support upgrade we were hoping for. Apple offers 90 days of free phone support and one year of repairs, but that's too skimpy; the phone support, especially, should be longer. For a reasonable $169, you can opt for the Apple Protection Plan at checkout to increase both plans to three years. If you're having trouble and the warranty period has ended, look to Apple's fine support pages, especially the user forums. Mac fanatics love to help others and are usually quick with worthwhile responses to problems.

Application performance
(Longer bars indicate better performance)
BAPCo SysMark 2004 rating  
SysMark 2004 Internet-content-creation rating  
SysMark 2004 office-productivity rating  
Dell XPS 400

Adobe Photoshop CS test (in seconds)
(Lower times are better)

Apple iTunes MP3-encoding test
(Lower times are better)

Sorenson Squeeze 4 video-encoding test (in seconds)
(Lower times are better)

Doom 3 Custom Demo 1,024x768, High Quality, with 4X antialiasing and 8X anisotropic filtering (in frames per second)
(Higher scores are better)

System configurations:
Apple iMac Core Duo (Mac OS X)
Macintosh OS 10.4.4; 2.0GHz Intel Core Duo; 1GB DDR2 SDRAM 667MHz; 128MB ATI Radeon X1600 PCIe; 250GB Maxtor 7,200rpm Serial ATA hard drive
Apple iMac Core Duo (Windows XP)
Windows XP Pro SP2; 2.0GHz Intel Core Duo; 1GB DDR2 SDRAM 667MHz; 128MB ATI Radeon X1600 PCIe; 250GB Maxtor 7,200rpm Serial ATA hard drive
Apple iMac G5 2.10GHz
Macintosh OS 10.4; PowerPC G5 2.10GHz; 512MB DDR2 SDRAM 533MHz; 128MB ATI Radeon X600XT PCIe; 250GB Serial ATA hard drive
Dell XPS 400 (Viiv)
Windows XP Media Center Edition 2005; 3.2GHz Intel Pentium D 940; Intel 945P chipset; 1,024MB DDR SDRAM 533MHz; 256MB Nvidia GeForce 6800 (PCIe); two Maxtor 250GB 7,200rpm Serial ATA; integrated Intel (RAID 1)
HP Pavilion Media Center TV m7360n
Windows XP Media Center Edition 2005; 2.8GHz Intel Pentium D 920; Intel 945G chipset; 2,048MB DDR2 SDRAM 533MHz; 256MB Nvidia GeForce 6200 SE (PCIe); Maxtor 300GB 7,200rpm Serial ATA


Apple iMac Core Duo

Score Breakdown

Design 9Features 9Performance 5Support 5