capsule review

Lab tested: 21.5- and 27-inch Core i3 iMacs/3.2GHz benchmarks

With Apple’s recent update of the iMac line, all new models now feature discrete graphic subsytems and Intel Core i3 and Core i5 processors. The two systems in this report are a step up from the $1199 21.5-inch 3.06GHz Core i3 iMac we tested on Wednesday. These two new systems use 3.2GHz Core i3 processors and have 1TB hard drives (up from 500GB on the new entry-level iMac) and the same 4GB of 1333MHz DDR3 SDRAM standard in all of the new iMacs. The 21.5-inch version is $1499, while the 27-inch version is $1699.

Using our overall system performance test suite, Speedmark 6, we found that the new 3.2GHz Core i3 iMacs, with scores of 188 for the 27-inch model and 190 for the 21.5-inch model, were 6 and 7 percent faster, respectively, than the entry-level 21.5-inch 3.06GHz Core i3 iMac.

That performance gap would be even smaller if we were to ignore the Handbrake 0.9.3 test, which was unusually slow on the 3.06GHz Core i3 iMac. We are doing some further testing with a newer version of the application (which was released just after Speedmark 6’s debut). The 3.06GHz Core i3 iMac we tested is using a HL (Hitachi-LG) optical drive, while the 3.2GHz models are using Pioneer optical drives. We’re also running additional tests with encoded files already ripped to the hard drive to eliminate any role that the optical drives may be playing in this performance peculiarity and hope to report on those findings tomorrow.

Both of the new 3.2GHz Core i3 iMacs posted Speedmark scores 16 percent faster than the 3.06 Core 2 Duo systems they replace, not bad for systems with identical price tags. The new systems showed marked improvement over their predecessors in many of our tests, including CineBench (28 percent), iTunes encode (22 percent), iMovie import (25 percent). The only test where an older Core 2 Duo bested the new crop was in our test of unzipping an archive in the Finder, with the older 27-inch iMac finishing the test 5 seconds faster than the newer 27-inch Core i3 iMac.

Comparing the new to last year’s top of the line iMac, a quad-core 27-inch model with 2.66GHz Core i5 processors, we found the older $1999 model to be 10 and 11 percent faster over all than the new 3.2GHz 21.5 and 27-inch models, respectively. The older quad-core system was 26 percent faster in our Cinebench test and 55 percent faster in our MathematicaMark test. Compressor, too, benefitted from the four cores, with about an 18 percent faster time.

We’re expecting our new 27-inch quad-core 2.8GHz Core i5 iMac tomorrow, so results should post soon. We're also working on full reviews of all the new iMacs, and we'll post those (with mouse ratings) as soon as possible.

21.5- and 27-inch iMacs Core i3/3.06GHz benchmarks

Mark 7
Call of
Duty 4
Finder Parallels
WorldBench 6
21.5" iMac 3.2GHz
Core i3
190 0:41 1:37 6.24 7:00 1:54 1:42 1:04 0:59 81.4 0:43 4:41 1:37 0:25
27" iMac 3.2GHz
Core i3
188 0:42 1:37 6.2 6:58 1:59 1:42 1:05 0:59 81.4 0:44 4:45 1:37 0:27
21.5" iMac 3.06GHz
Core i3
178 0:41 1:42 6.01 7:13 1:57 1:44 1:05 1:01 81.3 0:44 4:51 3:27 0:28
21.5" iMac 3.06GHz
Core 2 Duo
(ATI Radeon HD 4670)
164 0:41 2:15 4.42 8:06 2:32 2:16 1:18 1:16 69.1 0:43 5:20 2:20 0:32
27" iMac 3.06GHz
Core 2 Duo
162 0:42 2:15 4.28 8:16 2:34 2:17 1:16 1:16 66.2 0:39 4:45 2:23 0:32
27" iMac 2.66GHz
Core i5
209 0:39 1:12 9.64 5:44 1:50 1:22 1:03 1:07 86.9 0:43 5:07 1:22 0:26

Best results in bold. Reference systems in italics.

How we tested. Speedmark 6 scores are relative to those of a 2.13GHz Core 2 Duo MacBook, which is assigned a score of 100 (higher scores are better). Call of Duty score is in frames per second (higher is better). MathematicaMark is a performance score (higher is better). All others are in minutes:seconds (lower is better). The new Core i3 iMacs were tested with OS X 10.6.4. Both 3.06GHz Core 2 Duo iMacs were tested with OS X 10.6.1. The 27-inch 2.66GHz Core i5 iMac was tested with OS X 10.6.2. We duplicated a 1GB file, created a Zip archive in the Finder from the two 1GB files and then unzipped it. We converted 90 minutes of AAC audio files to MP3 using iTunes’ High Quality setting. In iMovie '09, we imported a camera archive and exported it to iTunes using the Mobile Devices setting. We ran a Timedemo at 1024-by-768 with 4X anti-aliasing on in Call of Duty 4. We imported 150 JPEGs into iPhoto '09. The Photoshop Suite test is a set of 14 scripted tasks using a 50MB file. Photoshop’s memory was set to 70 percent and History was set to Minimum. We used Compressor to encode a .mov file to the application's H.264 for video podcast setting. We ripped a DVD chapter to the hard drive. We recorded how long it took to render a scene with multiprocessors in Cinebench. We ran the Evaluate Notebook test in MathematicaMark 7. We ran the WorldBench 6 multitasking test on a Parallels 5 VM running Windows 7 Professional. We timed the import and thumbnail/preview creation time for 150 photos in Aperture.—Macworld Lab testing by James Galbraith, Mckinley Noble, Blair Hanely Frank, and Chris Holt.

[James Galbraith is Macworld’s lab director.]

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