Apple iMac review: A trimmed-down, amped-up new iMac

Performance
Our performance comparison will seem unfair given that we do not have results for the $2,599 Dell XPS One 27, a system with the same CPU as our iMac review unit, as well as more memory and its own solid-state hard drive. The iMac has a faster graphics card, which helps to a certain extent on Photoshop, but otherwise I'd expect the highest-end Dell would post similar, if not better performance results than the iMac. If we can't make a direct speed comparison with the fastest XPS One 27, we can still say that the Dell and the iMac occupy a class by themselves compared with other 27-inch all-in-one PCs (all of which have lower-resolution 1,920x1,080-pixel displays).

The iMac's most decisive victory comes on our iTunes and QuickTime processing test, but that test tends to skew in Apple's favor, and I include it here mostly for comparison with the previous-generation iMac. The OS-agnostic version of that test with HandBrake (which we're phasing in to replace the QuickTime version), puts the Dell and the new iMac in much closer proximity to each other.

I won't say that the iMac walks away with the high-end all-in-one application performance crown, especially with the lurking specter of the higher-end Dell. Suffice it to say that this is the fastest iMac yet, and one of, if not the, fastest all-in-ones available.

On the graphics side, the iMac GeForce GTX 680 MX is the top-tier mobile graphics chip, and the most powerful GPU available in any all-in-one that isn't the HP Z1. I tested with Borderlands 2 at full 2,560x1,440-pixel resolution and maximum image quality and experienced no difficulty. I also tried the Witcher 2, one of the most demanding games available for OS X. I won't say it hit 60 frames per second, but it was more than playable, at full resolution and with ultra quality settings. For every other game on the Mac, and even most titles in a virtualized Windows environment, you should be able to play anything you come across with sufficient image quality.

The only other testing I would like to circle back on is a set of true display quality tests between the iMac and the XPS One 27. I hope we can put something together in the next few days, and I will update this review with any findings. Anecdotally, our photo editor was impressed by the iMac's apparent color gamut, as well as the level of detail within its black levels.

Two other performance notes worth mentioning. Our iMac includes a Fusion Drive, which means it has a 1TB mechanical hard drive and a 128GB solid-state drive joined in a single 1.2TB drive volume. Apple has designed Fusion so that it's seamless. The OS itself, as well as the files you use most frequently, load from the solid-state drive. The idea of Fusion is that it speeds up application loading, files transfers, and pretty much any drive-related system activity.

You can refer to our review of Apple's new Mac Mini for a deeper dive into Fusion, including some test results. Given the identical drive hardware, I expect that the performance will be the same on this iMac. The bottom line is that launching pretty much anything on the system happens almost instantly.

I can also credit the iMac's new, second microphone. Situated on the back of the display, the extra mic is there to help with canceling out background noise. In a FaceTime call, the recipient reported that my voice came through with no apparent backing hiss, even when I spoke from 15 feet away. She did mention that my voice became softer at that distance, understandably. She also heard some noise during dead air, similar to what you hear in the background during a conference room speakerphone.

Conclusion
You might be alarmed by the fact that the design is the most interesting thing about the new iMac. A thin bezel is nice to look at, but it doesn't improve processing speed, workflow, or overall utility. Fortunately for Apple, it evolved that design from a computer with a strong technical foundation. It is the updates to that foundation, and a few points of polish along the way, that keep this iMac on elite footing. I'll suggest you line up behind the Blu-ray fans to those of you hoping Apple will someday add touch-screen input to the iMac. Instead, this is a computer for serious, performance-driven users, particularly those who need a high-resolution display, and fast graphics and disk performance.

Performance testing conducted by Joseph Kaminski. Find out more about how we test desktop systems.

System configurations

Apple iMac 27-inch (December 2012)
Apple OS X Mountain Lion 10.8; 3.4GHz Intel Core i7-3770; 8GB 1,600MHz DDR3 SDRAM; 2GB Nvidia GeForce GTX 680M graphics card; 1TB 7,200rpm hard drive, 128GB solid-state hard drive

Acer Aspire 7600U
Microsoft Windows 7 Home Premium 64-bit (SP1); 2.5GHz Intel Core i5-3210M; 8GB 1,333MHz DDR3 SDRAM; 768MB Nvidia GeForce GT 640M graphics card; 1TB 5,400rpm hard drive

Apple iMac 27-inch (May 2011)
Apple OS X Snow Leopard 10.6.7; 3.1GHz Intel Core i5 (second generation); 4GB 1,333MHz DDR3 SDRAM; 1GB ATI Radeon HD 6970M graphics card; 1TB 7,200rpm hard drive

Asus ET2700I
Microsoft Windows 7 Home Premium 64-bit (SP1); 2.8GHz Intel Core i7-2600S; 8GB 1,333MHz DDR3 SDRAM; 1GB Nvidia GeForce GT 540M graphics card; 1TB 7,200rpm hard drive

Dell XPS One 27
Microsoft Windows 8 Pro 64-bit; 3.1GHz Intel Core i7-3770S; 8GB 1,600MHz DDR3 SDRAM; 2GB Nvidia GeForce GT 640M graphics card; 2TB 7,200rpm hard drive

Lenovo IdeaCentre A720
Microsoft Windows 7 Home Premium 64-bit (SP1); 2.5GHz Intel Core i5-3210M ; 6GB 1,333MHz DDR3 SDRAM; 1GB Nvidia GeForce GT 630M graphics card; 500GB 7,200rpm hard drive

Vizio CA27-A1
Microsoft Windows 7 Home Premium 64-bit (SP1); 2.5GHz Intel Core i5-3210M; 4GB 1,333MHz DDR3 SDRAM; 1GB Nvidia GeForce GT 640M LE graphics card; 1TB 7,200rpm hard drive