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Apple 21.5" iMac Quad-Core Intel Core i5 2.7GHz (4th generation Haswell processor), 8GB RAM, 1TB Hard Drive, Intel Iris Pro graphics, 2 Thunderbolt ports, 802.11ac Wi-Fi, Apple Wireless Keyboard, Magic Mouse, Mac OS X Yosemite - Mid 2013.

Quad-Core Intel Core i5 2.7GHz, 8GB (2x4GB) DDR3 SDRAM, 1TB SATA HDD, 21.5" LED-backlit, Intel Iris Pro graphics, Four USB 3 ports, SDXC card slot, Gigabit Ethernet, 802.11ac Wi-Fi wireless networking, Bluetooth 4.0 wireless technology.

CPU: Intel Core i5 Quad-Core 2.70 GHz
Memory: 8 GB
Keyboard: Apple Wireless Keyboard
Storage: 1 TB
Video Card: Intel Iris Pro Graphics 

Price: $1,229



Apple 21.5" iMac Quad-Core Intel Core i5 2.9GHz, 8GB RAM, 1TB Hard Drive, NVIDIA GeForce GT 750M graphics processor with 1GB of GDDR5 memory, Two Thunderbolt ports, Apple Wireless Keyboard and Magic Mouse, Mac OS X Yosemite (Mid 2013).

Quad-Core Intel Core i5 2.9GHz, 8GB (2x4GB) DDR3 SDRAM, 1TB SATA HDD, 21.5" LED-backlit, NVIDIA GeForce GT 750M graphics with 1GB, Four USB 3 ports, SDXC card slot, Gigabit Ethernet, 802.11ac Wi-Fi wireless networking, Bluetooth 4.0 wireless technology.

CPU: Intel Core i5 2.9 GHz
Memory: 8 GB
Keyboard: Apple Wireless Keyboard
Storage: 1 TB
Video Card: NVIDIA GeForce GT
Price: $1,399



Apple 27" iMac with Retina 5K display, Quad-Core Intel Core i7, 4.0GHz, 16GB RAM, 3TB Fusion Drive, AMD Radeon R9 M290X with 2GB of GDDR5 memory, Two Thunderbolt 2 ports, 802.11ac Wi-Fi, Apple Wireless Keyboard, Magic Mouse - Late 2014.

Quad-Core Intel Core i7 4.0GHz, 16GB DDR3 SDRAM, 3TB Fusion Drive, Four USB 3 ports, SDXC card slot, Gigabit Ethernet, 802.11ac Wi-Fi wireless networking, Bluetooth 4.0 wireless technology.

CPU: Intel Core i7 Quad-Core 4 GHz
Memory: 8 GB
Keyboard: Apple Wireless Keyboard
Storage: 1 TB
Video Card: AMD Radeon R9 M290X

Price: $3,549



The 2015 Apple iMac ($1,999 as tested) features a brilliant 5K Retina In-Plane Switching (IPS) display backed by a beefy Intel Core i5 processor and AMD R9 graphics.

It's the system to get if you perform a lot of tasks that require insane levels of visual detail, like graphics, photography, scientific analysis, and video. And now Apple has made it more affordable to own one. Thus, it earns our Editors' Choice for high-end all-in-one desktops.

The 8GB of system memory and 1TB of hard drive storage are more than adequate for intricate graphics work. The Fusion Drive is available as an option on the base configuration we reviewed, but it comes standard with the top-of-the-line iMac. Fusion Drive is a self-regulating combination of Flash Storage memory and a 1TB spinning hard drive. 

The slower hard drive holds data and apps you don't use very often, while the smaller 128GB of Flash Storage quickly loads the operating system and the apps and files you use everyday. If you need more memory, a hatch opens on the back of the desktop, exposing two free DIMM slots, letting you easily increase the RAM to a maximum of 32GB. You can't as simply upgrade the system's hard drive, however. It is doable with a lot of time and determination, but you'll need specialized tools to get into the chassis. It's much easier to upgrade the storage from a selection of Flash Storage and Fusion Drive options when you order the system.

from pcmag.com