Apple iMac Core Duo (20-inch, 2.0GHz) review

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.

First the good news. On our iTunes test, the iMac Core Duo 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 per cent, to be precise). Similarly, the iMac Core Duo showed an improvement on our Doom 3 test, posting 16.2 frames per second at 1,024x768 pixels, compared to the iMac G5's 11.6. That's not a significant increase, nor is it even a playable frame rate, but note that Doom 3 is a non-native application. The speed increase is probably 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 non-natively, we think it's reasonable to expect that if a native version emerges, you'll see an even larger performance gain.

Still, it's not all roses for the iMac Core Duo. Our Mac tests focus exclusively on multimedia performance, so for less-demanding programs such as Microsoft Office, the non-native performance picture might not be as dire. But if you want to run Photoshop or a non-native video-encoding program such as Sorenson Squeeze, we highly recommend you wait until the software catches up before purchasing a new iMac Core Duo.

On Photoshop, the iMac Core Duo was 81 per cent slower than the iMac G5, taking 6 minutes 30 seconds to run our photo script compared to the iMac G5's 3 minute 36 seconds. The Sorenson scores were even worse, to the tune of a whopping 463 per cent difference. The iMac G5 took 5 minutes 11 seconds to complete our test. The iMac Core Duo? An unacceptable 24 minutes.

There's 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 auto-update 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 non-native scores alarming, you're not alone. But 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.

Edited by Matthew Elliott
Additional editing by Nick Hide