LED Backlighting
When a display has more pixels, you need to push more light through them to achieve the best picture possible. LED backlighting in the new iMac does exactly that, with remarkable brightness and efficiency. Because the LED backlight doesn’t take up much space, the iMac enclosure stays thin — even with all the high-performance components inside.
Higher Resolution
The new 21.5-inch iMac features 1920-by-1080 HD resolution, while the 27-inch iMac features 2560-by-1440 resolution. That’s 78 percent more pixels than the 21.5-inch iMac.
IPS Technology
The iMac display is designed to look great from almost any angle. A technology called in-plane switching (IPS) makes this possible. Whether you’re sitting in front of the display or standing off to the side, you’ll get a perfect picture with superb color consistency and no loss of detail.
Seamless Enclosure
While you’ll find a collection of ports on the back of iMac, you won’t find much else. A seamless, precision-forged enclosure makes the back one continuous aluminum surface. And there’s only one cord: the power cord.
Cool & Quiet
The wider iMac display allows more room to separate the two hottest components, the CPU and the GPU. This keeps things cool inside the iMac enclosure. Apple engineers also implemented an intelligent control system that monitors temperatures and delivers just the right amount of airflow to critical components. And the three fans inside iMac have been tuned to be ultraquiet. A system that operates at 18 decibels when idle — so quiet, you hardly know it’s on.
Wireless Keyboard & Mouse
iMac embodies simple design that eliminates desktop clutter. So naturally, it’s the first Mac to come standard with the Apple Wireless Keyboard and the new wireless Magic Mouse.
Multi-Touch Technology
Magic Mouse is designed to do all the things a mouse should do — pointing, clicking, and scrolling — but with no scroll wheel, no trackball, and no visible button. Magic Mouse uses Multi-Touch technology to let you click, scroll, or swipe anywhere on its perfectly smooth, seamless top shell. But the real magic of Magic Mouse is how it knows what you want to do. A chip inside Magic Mouse acts as a brain, detecting the difference between a resting hand, a scrolling finger, a two-finger swipe, and a simple click.
iMac Graphics
21.5 Inch
Basic: Integrated NVIDIA GeForce 9400M
Upgrade: ATI Radeon HD 4670
256MB of GDDR3 memory
Up to 4x faster performance than NVIDIA GeForce 9400M
Gives you better gaming performance and better responsiveness for video and photo editing.
27 Inch
Basic: ATI Radeon HD 4670
Upgrade: ATI Radeon HD 4850
512MB of GDDR3 memory
Up to 1.8x faster performance than ATI Radeon HD 4670
Gives you the fastest, most responsive graphics for photo editing with Aperture, animation with Motion, and graphics-intensive 3D games like Call of Duty.
P.S: The info and the details are gathered from Apple.
