Apple Readying iMac Retina with 5K Display
 

Apple's next iMac desktop could flaunt the company's "Retina Display" moniker, which stands for pixel density that matches that of your retina. Apple's idea of Retina display on a 20-something inch desktop is 5K, which is 5120 x 2880 pixels, or four times the resolution of WQHD (2560 x 1440), or sixteen times HD (1280 x 720). Early betas of Apple's OSX "Yosemite" feature references to display resolutions upwards of 5K, including 5760 x 3240, and 6400 x 3600.

At 27-inch, 5120 x 2880 would give the Mac a staggering 217 ppi of pixel density, which is not very far from the 263 ppi which 9.7-inch iPads offer, with their 2048 x 1536 resolutions. To put 217 ppi into perspective, a 28-inch Ultra HD display offers 157 ppi, and Apple's current 27-inch iMac with WQHD display offers just 108 ppi. A mainstream 24-inch full HD (1920 x 1080) display offers just 91 ppi. The GPUs that drive these next-gen iMacs are anyone's guess. Both current-generation AMD, and NVIDIA's new GTX 980 cap out at digital resolutions of 4096 x 2160.

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