Faster than ever: Macworld Lab speed tests the mid-2011 iMacs

Products Reviewed

(4 items)

We’ve already shared the results of our benchmark tests for the $1999 27-inch 3.1GHz Core i5 iMac, one of four new iMac configurations released by Apple this week. We’ve had the chance to finish testing the remaining three standard-configuration models, with our results showing a significant boost for the new iMacs over the models they replace. However, not much differentiates the performance of the four new iMacs among each other.

The new entry-level iMac is a 21.5-inch, $1199 model with a 2.5GHz Core i5 quad core processor, a 500GB hard drive, and AMD Radeon HD 6750M graphics with 512MB of video memory. The other 21.5-inch iMac has a 2.7GHz Core i5 quad core processor, a 1TB hard drive, and AMD Radeon HD 6770M graphics with 512MB of video memory for $1499. A 27-inch iMac with otherwise identical specifications to the $1499 iMac costs $1699. And finally, the previously benchmarked 27-inch iMac is a $1999 system with a 3.1GHz Core i5 quad core processor, a 1TB hard drive, and AMD Radeon HD 6970M graphics with 1GB of video memory. All four systems run on Sandy Bridge processors from Intel.

Macworld Lab’s overall system performance test suite, Speedmark 6.5, showed these four new Sandy Bridge iMacs to be considerably faster than the systems they replace. The new $1199 21.5-inch, 2.5GHz Core i5 quad core iMac was nearly 24 percent faster overall than last year’s entry-level 21.5-inch iMac, which had a 3.06GHz Core i3 dual core processor. As you would expect, the new iMac showed the most improvement in applications that could take advantage of four processing cores. The new entry-level system was 37 percent faster in our Handbrake encoding test, 34 percent faster in our Cinebench CPU test, and 64 percent faster in MathematicaMark.

The new $1199 iMac was even faster than last year’s high-end standard configuration model, a 27-inch 2.8GHz Core i5 quad core iMac, by nearly 10 percent. In this case, the processor-intensive tests were very close, but the file duplication, zipping and unzipping a folder and opening a Word document in Pages were all considerably faster on the new $1199 iMac.

Compared to the 27-inch 3.2GHz Core i3 dual core iMac from last year, the new $1699 iMac was 25 percent faster. The older 3.2GHz Core i3 iMac also performed better than the new 2.7GHz Core i5 iMac in its file duplication and unzip tasks, but everything else was faster—sometimes much faster—on the new 2.7GHz system. Handbrake was 40 percent faster on the new model, Cinebench CPU tests were 37 percent faster, and MathematicaMark scored 70 percent higher.

iMac (Mid-2011) benchmarks

	Speedmark 6.5 Score
21.5-inch iMac Core i5 2.5GHz	215
21.5-inch iMac Core i5 2.7GHz	223
27-inch iMac Core i5 2.7GHz	222
27-inch iMac Core i5 3.1GHz	227
21.5-inch iMac Core i3 3.06GHz (Mid 2010)	174
21.5-inch iMac Core i3 3.2GHz (Mid 2010)	179
27-inch iMac Core i3 3.2GHz (Mid 2010)	177
27-inch iMac Core i5 2.8GHz (Mid 2010)	196
27-inch iMac 2.93GHz Core i7 (BTO, Mid 2010)	225
27-inch iMac 3.6GHz Core i5 (BTO, Mid 2010)	199
21.5-inch iMac 3.06GHz Core 2 Duo (Late 2009)	129
27-inch iMac 2.66GHz Core i5 (Late 2009)	195
15-inch MacBook Pro 2.2GHz Core i7 (Early 2011)	206
Mac Pro 3.33GHz Xeon Westmere six-core (BTO, Mid 2010)	*263*

Higher scores are better. Reference models in italics. Best result in bold.

Surprisingly, when compared to each other, the new iMacs logged similar performance numbers. In fact, only 12 Speedmark points separate the entry-level $1199 21.5-inch 2.5GHz Core i5 iMac and the top-of-the-line $1999 27-inch 3.1GHz Core i5 iMac.

Looking at the new $1699 27-inch 2.7GHz Core i5 quad core iMac, we see that it outperforms the entry-level $1199 system by just 4 percent, overall. The close scores can be attributed to the 500GB hard drive in the $1199 model which was faster at file duplication and unzipping folders than the other three models with their 1TB hard drives. iMovie, iTunes, Photoshop, Handbrake, Cinebench, and Mathematica were faster on the $1699 system.

The new 27-inch 2.7GHz system—which uses the same processor, graphics and hard drive as the 21.5-inch 2.7GHz iMac—performed nearly identically to that model.

We initially completed all of our tests before Apple released the Mac OS X 10.6.7 Update for iMac and the iMac EFI Update 1.6. We retested with the updates installed, and found no difference in performance with our tests.

Speedmark 6.5 individual application test results:
New iMacs (Mid 2011)

	Duplicate 1GB File	Zip 2GB folder	Unzip 2GB folder	Pages '09 Open Word Doc
21.5-inch iMac Core i5 2.5GHz	18	147	36	70
21.5-inch iMac Core i5 2.7GHz	20	134	47	65
27-inch iMac Core i5 2.7GHz	20	133	45	65
27-inch iMac Core i5 3.1GHz	20	144	48	70
21.5-inch iMac Core i3 3.06GHz (Mid 2010)	19	166	42	77
21.5-inch iMac Core i3 3.2GHz (Mid 2010)	19	160	42	67
27-inch iMac Core i3 3.2GHz (Mid 2010)	20	161	43	76
27-inch iMac Core i5 2.8GHz (Mid 2010)	21	170	44	76
27-inch iMac 2.93GHz Core i7 (BTO, Mid 2010)	17	157	36	71
27-inch iMac 3.6GHz Core i5 (BTO, Mid 2010)	17	140	36	65
21.5-inch iMac 3.06GHz Core 2 Duo (Late 2009)	20	177	40	85
27-inch iMac 2.66GHz Core i5 (Late 2009)	22	179	43	76
15-inch MacBook Pro 2.2GHz Core i7 (Early 2011)	23	159	50	76
Mac Pro 3.33GHz Xeon Westmere six-core (BTO, Mid 2010)	18	148	26	62

Results are in seconds. Lower results are better. Reference models in italics. Best result in bold.

Speedmark 6.5 individual application test results:
New iMacs (Mid 2011)

	iTunes 10 AAC to MP3 encode	Import movie archive to iMovie '09	iMovie '09 export to iTunes 10 for iPhone	Call of Duty 4 framerate
21.5-inch iMac Core i5 2.5GHz	83	76	55	86.3
21.5-inch iMac Core i5 2.7GHz	74	71	49	87.6
27-inch iMac Core i5 2.7GHz	75	72	53	88.1
27-inch iMac Core i5 3.1GHz	74	66	51	88.5
21.5-inch iMac Core i3 3.06GHz (Mid 2010)	95	103	69	78.3
21.5-inch iMac Core i3 3.2GHz (Mid 2010)	91	101	68	78.4
27-inch iMac Core i3 3.2GHz (Mid 2010)	91	100	68	78.2
27-inch iMac Core i5 2.8GHz (Mid 2010)	95	78	56	88.1
27-inch iMac 2.93GHz Core i7 (BTO, Mid 2010)	92	61	55	88.3
27-inch iMac 3.6GHz Core i5 (BTO, Mid 2010)	80	90	61	79.0
21.5-inch iMac 3.06GHz Core 2 Duo (Late 2009)	123	97	102	19.1
27-inch iMac 2.66GHz Core i5 (Late 2009)	101	82	60	87.5
15-inch MacBook Pro 2.2GHz Core i7 (Early 2011)	83	70	55	81
Mac Pro 3.33GHz Xeon Westmere six-core (BTO, Mid 2010)	81	48	48	88.3

Call of Duty 4 results are based on framerate; higher results are better. All other test results in the above chart are in seconds; lower results are better. References models in italics. Best result in bold.

Speedmark 6.5 individual application test results:
New iMacs (Mid 2011)

	iPhoto '09 200 JPEG import	Photoshop CS5 action	HandBrake 0.9.4 encode	Cinebench R11.5 graphics
21.5-inch iMac Core i5 2.5GHz	32	54	254	36
21.5-inch iMac Core i5 2.7GHz	33	52	236	41.6
27-inch iMac Core i5 2.7GHz	33	52	236	40.2
27-inch iMac Core i5 3.1GHz	28	53	209	38.3
21.5-inch iMac Core i3 3.06GHz (Mid 2010)	35	60	405	25.4
21.5-inch iMac Core i3 3.2GHz (Mid 2010)	34	58	391	27.4
27-inch iMac Core i3 3.2GHz (Mid 2010)	35	59	392	27.3
27-inch iMac Core i5 2.8GHz (Mid 2010)	36	55	256	31.9
27-inch iMac 2.93GHz Core i7 (BTO, Mid 2010)	29	53	208	34.8
27-inch iMac 3.6GHz Core i5 (BTO, Mid 2010)	33	55	340	31.0
21.5-inch iMac 3.06GHz Core 2 Duo (Late 2009)	42	62	569	6.4
27-inch iMac 2.66GHz Core i5 (Late 2009)	38	57	267	30.7
15-inch MacBook Pro 2.2GHz Core i7 (Early 2011)	52	55	220	35
Mac Pro 3.33GHz Xeon Westmere six-core (BTO, Mid 2010)	27	55	*144*	34

CineBench R11.5 Graphics results are a score; higher results are better. All other test results in the above chart are in seconds; lower results are better. Reference models in italics. Best result in bold.

Speedmark 6.5 individual application test results:
New iMacs (Mid 2011)

	Cine- bench R11.5 CPU	Mathe- matica Mark 7	Parallels World- Bench Multitask test	Aperture 3 import and process	Multi- tasking
21.5-inch iMac Core i5 2.5GHz	103	10.0	287	108	63
21.5-inch iMac Core i5 2.7GHz	96	10.7	262	104	61
27-inch iMac Core i5 2.7GHz	96	10.6	263	111	60
27-inch iMac Core i5 3.1GHz	85	11.7	247	107	58
21.5-inch iMac Core i3 3.06GHz (Mid 2010)	157	6.1	340	125	78
21.5-inch iMac Core i3 3.2GHz (Mid 2010)	152	6.3	333	121	75
27-inch iMac Core i3 3.2GHz (Mid 2010)	152	6.23	332	123	75
27-inch iMac Core i5 2.8GHz (Mid 2010)	108	10.1	290	118	65
27-inch iMac 2.93GHz Core i7 (BTO, Mid 2010)	77	12.5	282	108	62
27-inch iMac 3.6GHz Core i5 (BTO, Mid 2010)	130	7.0	293	109	72
21.5-inch iMac 3.06GHz Core 2 Duo (Late 2009)	229	4.3	355	137	88
27-inch iMac 2.66GHz Core i5 (Late 2009)	112	9.7	300	118	65
15-inch MacBook Pro 2.2GHz Core i7 (Early 2011)	81	11.4	278	118	61
Mac Pro 3.33GHz Xeon Westmere six-core (BTO, Mid 2010)	48	19.2	253	101	59

MathematicaMark 7 results are scores; higher results are better. All other test results in the above chart are in seconds; lower results are better. Reference models in italics. Best result in bold.

How we tested. Speedmark 6.5 scores are relative to those of a 2.4GHz Core 2 Duo Mac mini (Mid 2010) with 2GB of RAM, which is assigned a score of 100. We duplicated a 1GB file, created a Zip archive in the Finder from the two 1GB files and then unzipped it. We converted 135 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 200 JPEGs into iPhoto '09. The Photoshop Suite test is a set of 23 scripted tasks using a 50MB file. Photoshop’s memory was set to 70 percent and History was set to Minimum. For our multitasking test, we timed the Photoshop test again, but with the iTunes MP3 encoding and file compression tests running in the background. We used Handbrake to encode four chapters from a DVD previously ripped to the hard drive to H.264. We recorded how long it took to render a scene with multiprocessors in Cinebench and ran that application's OpenGL, frames per second test. We ran the Evaluate Notebook test in MathematicaMark 7. We ran the WorldBench 6 multitasking test on a Parallels 6 VM running Windows 7 Professional. We timed the import and processing time for 200 photos in Aperture.—Macworld Lab testing by James Galbraith, William Wang, and Mauricio Grijalva

Keep in mind we’ve only tested the standard configurations so far. The new iMacs offer several build-to-order options including faster processors and solid-state drives (either as a replacement for or complement to the main drive). That latter option, in particular, could lead to some performance swings; we plan on testing the build-to-order iMacs as soon as we finish reviewing the base models.

Check back soon for Macworld’s full review of the new line of iMacs, including more graphics tests.

[James Galbraith is Macworld’s lab director.]