The new 21.5-inch iMac with 4K Retina display has only been out this week, but testers are already impressed with Apple's latest-gen desktop computer. The same acclaim was also given to its 27-inch 5K launch partner.

The latest benchmark listing on GeekBench's database shows the new iMacs outperforming previous iMac models by up to seven to 20 percent. However, the results are still partial since they are based on single data points that still needs to be averaged against other benchmark results. Even so, the preliminary results are indicative of how drastic iMac technology can improve in a span of a year.

Specifically, the new 21.5-inch 4K iMac powered by the 3.1GHz quad-core Intel Core i5-5675R processor tallied a single-core score of 3,787 and a multi-core score of 12,803. In comparison, Mac Otakara, via Mac Rumors, pointed out that the 2.9GHz iMac model from late 2013 received single-core and multi-core scores of 3,543 and 10,685 respectively.

The updated 27-inch 5K iMacs models also surpassed their predecessors considerably. The 3.2GHz quad-core Intel Core i5-6500 model topped the latest benchmark with single-core and multi-core scores of 3,931 and 12,079. Its counterpart from 2014 received a single-core score of 3,329 and multi-core score of 10,632.

Meanwhile, the 27-inch 5K iMac clocked at 3.3GHz and powered by the Intel Core i5-6600 processor garnered a single-core score of 4,214 and multi-core score of 13,081. The comparable high-end 5K iMac equipped with the Intel Core i5-4590 processor from mid-2015 raked single-core and multi-core scores of 3,844 and 12,192.

Apple launched the new iMacs on Tuesday, Oct. 13. The Cupertino tech giant said that the new 21.5-inch 4k iMac has 4.5 times more pixels than the standard 21.5-inch iMac.

Its new panel displays more vivid colors while its two Thunderbolt 2 ports is capable of transferring data up to 20 Gbps, Apple Insider reported.

"From the first iMac to today, the spirit of iMac has never wavered - deliver the ultimate desktop experience with the latest technologies, gorgeous displays and cutting-edge designs," said Apple's marketing executive Philip Schiller.

"These are the most stunning iMacs we've ever made. With our gorgeous new Retina displays, more powerful processors and graphics and all-new Magic accessories, the new iMac continues to redefine the ultimate desktop experience."

Prices for the 21.5-inch 4K iMac and its larger 27-inch 5K sibling starts at $1,500 and $2,300 respectively.

The setup is inclusive of Apple's new Magic Mouse 2 and Magic Keyboard while the new Magic Trackpad is sold separately. Interested buyers can head over to Apple to avail of the new accessories.