I've been using Apple's new iMac with Retina 5K display for the last few days. I'm now convinced all the positive reviews are correct -- this is a fabulous Mac capable of high-end performance and equipped with an utterly compelling display. I've curated a few details you might not be aware of concerning the top-of-the-line iMac.
The process Apple uses to manufacture the unibody aluminium chassis is called friction welding, which the company first brought to market in 2013.
The Mac delivers seven times the number of pixels you'll find on an HDTV at 445 cd/m^2 full brightness. It offers 14.7 million pixels (at a resolution of 5,120-x-2,880); the conventional 27-in. model resolution is 2,570-x-1,440.
Check the small print
Equivalent 5K displays will set you back $2,500+ for the display alone -- and may not be as good. Apple uses IPS technology, while cheap 4K displays use inferior TN technology. Check the small print.
Apple worked with Parade Technologies to design its own display timing controller (above) to send signal to the pixels on the display. LG manufactures some of the displays.
A new timing controller was required in order to handle the bandwidth demands of 5K -- even Thunderbolt 2 can't handle that kind of load yet, which is why there's no 5K Cinema Display.
That timing controller means the iMac operates at 60Hz in native 5,120-x-2,880 resolution. Clever.
Apple claims the 1.4mm display panel assembly features 23 layers of technological innovation, including a new oxide-based TFT which helps ensure solid contrast even when viewing the display off-axis.
Mobile pervades everything at Apple today -- the high-end AMD Radeon R9 M295X GPU delivers amazing performance, but is designed as a mobile system. You'll get excellent graphics from the 2GB dedicated video memory.
iMac features an iPad technology ("overpass"), which reduces operational interference, and helps maintain image quality. The display consumes 30% less power than previous generation iMac displays.