There's still no news on when the new iMac 2016 will come out, but that doesn't prevent websites from sharing several rumors on the Apple desktop.

The last time the iMac was updated was on Oct. 13 last year with the Retina and the Skylake processors.

According to MacWorld, the last time there was significant update on the iMac was in September 2013 with the introduction of the new graphics, Haswell processor, PCIe flash storage and next-gen WiFi.

With the Retina and Skylake, it said that Apple announcing new update on the iMac 2016 is unlikely considering that it would be less than a year since the September 2013 upgrade.

Historically, Apple has three major events where it unveils its products. That would be in March (MacBooks or watches), the WWDC event in June-for its OS updates--and September for its iPhone and iPad lines.

Does that lend credence to the rumors that the iMac 2016 would be unveiled in October in a separate press event? There's no word on that yet, but major upgrades have a two-year gap between them. it could mean the WWDC next year.

Previous news reports and rumors pointed to the Polaris graphics chipset 400-series heading to the iMac 2016. The Retina iMac and 15-inch Retina MacBook Pro already made use of the AMD 200/300 series GPUs, which is a significant upgrade 28nm GPU.

Radeon Technologies Group chief architect Raja Koduri said the new chipsets would drastically improve performance of any PC. "We are really focusing on trying to bring FinFET technology with its amazing performance per watt to as many segments as possible," he said.