Apple's rumored Oct. 16 special event is expected to be the company's platform to unveil a new line of iPads as well as a Retina iMac release date for a new 2014 lineup of the all-in-one desktop computer, featuring a 5K resolution display and OS X Yosemite.

"A new line of iMacs with ultra high-resolution Retina Displays is in late testing stages within Apple, according to our sources who have used the future desktop computer. While the machine will sport a thin profile similar to that of the current design, which was introduced in 2012, it will be packed with new internals such as faster processors and improved WiFi antennas," 9to5Mac reported.

In June, Apple launched a cheaper 21.5-inch iMac featuring ultra-thin design, 1.4 GHz dual-core Intel Core i5 processor, Intel HD 5000 graphics, 8 GB memory and 500 GB hard drive.

The cheaper iMac has a price tag of $1,099 (starting price), which is thought to appeal to a broader and more frugal audience.

The trademark Retina Display technology was introduced by Apple in 2010 with iPhone 4, and extended to iPad and Macbook Pro in 2012.

It has been a while since Apple injected fresh energy to their desktop lineup.

For this reason, the integration of Retina Display can bring a significant improvement to the "functional" side of the device.

Reports mention that the new Retina iMac will keep the same chassis of the current iMac, but will add updated versions of iMovie and Final Cut Pro.

Since OS X Yosemite is also being pitched for an October release, its betas offer some ideas as to what to expect with the Retina iMac 5K resolution models including 6400 x 3600, 5760×3240, and 4096×2304 resolution displays, respectively.