CPU CRUNCH SHOOTOUT:

iMac Core i7 versus other Macs

Posted Monday, November 16th, 2009, by rob-ART morgan, mad scientist

Updated, November 19th, 2009 with iMac Core i5 results

We, like many of you, are excited about the new quad-core iMacs. We ordered the "Core i7" model and decided to compare it not only to the fastest dual core iMac but also to the quad-core and octo-core 'early 2009' Mac Pro (Nehalem).

GRAPH LEGEND

MP 8core = 8-core 'early 2009' Mac Pro 2.93GHz with 12G of RAM and Radeon HD 4870

MP 4core = 4-core 'earl 2009' Mac Pro 2.93GHz with 12G of RAM and Radeon HD 4870

i7 iMac = 4-core 'late 2009' iMac 2.8GHz Core i7 with 8G of RAM and Radeon HD 4850

i5 iMac = 4-core 'late 2009' iMac 2.66Ghz Core i5 with 8GB of RAM and Radeon HD 4850

c2c iMac = 2-core 'early 2009' iMac 3.06GHz Core 2 Duo with 8G of RAM and Radeon HD 4850

TEST APPS: Cinebench 10, Geekbench 2.1.4, Compressor 3.0.5, After Effects CS4.

RED BAR means FASTEST

"Gap Spanner"

The iMac Core i7 (quad-core) finally gives us an "all in one" Mac that can "run with the big dogs." It is just a few steps behind the 2.93GHz quad-core Mac Pro and significantly faster than the fastest dual-core iMacs -- at least when running "MP aware" software. With memory expansion up to 16GB, drive options up to 2TB, Radeon HD 4850 graphics, and a 27" LED display, there is very little else you would want if you are a fan of "all in one."

Considering the fact that a four-core Mac Pro 2.93GHz with 8GB of RAM, 1TB HDD, Radeon HD 4870, and 24" LED Cinema display lists at $4448 while the iMac Core i7 2.8GHz with 8GB of RAM, 1TB HDD, Radeon HD 4850, and 27" LED display lists at $2399, the four-core iMac is a huge bargain.

What about the Core i5 iMac? Based on the four CPU intensive apps featured in the graphs, we believe it's well worth paying 10% more for the Core i7 iMac to get 13% to 30% more CPU crunching power.

The only "missing piece" in the lastest model of iMac is an external eSATA port. That would enable owners to take advantage of the speed offered by HDD enclosures with 7K SATA drives capable of 138MB/s and/or Port-Multiplier multi-bay SATA enclosures capable of 230+MB/s. I'm sorry but FireWire 800 at a maximum of 80MB/s seems lame nowadays.

The Core i7 (and i5) have "Turbo Boost" which increases the core clock speed when only one or two cores are active. We may have observed that phenom when we ran the single CPU test in Cinebench. In that scenario, the 2.8GHz Core i7 was 21% faster than the 3.06GHz Core 2 Duo.

We also are just getting started with testing the Core i5 and i7 iMac, so stay tuned for more fascinating results.