One product category that has continued to perform quite well for Apple (AAPL -0.57%) is the Mac. Even as the broader PC market continues to decline, Apple has posted multiple quarters of year-over-year growth, suggesting continued market segment share gains against Windows-based personal computers.

According to generally reliable analyst Ming-Chi Kuo, Apple will be updating its iMac line of desktop all-in-one computers later this quarter. Let's take a closer look at what Apple might be bringing to the table.

Better display, faster processors
Kuo predicts that the new iMacs will have "more powerful processors" as well as "much better display quality." In particular, he believes that the display in the new iMacs will use an "LED phosphor material called KSF to notably boost color saturation."

In particular, according to a report from IHS analyst Jimmy Kim, Ph.D, KSF phosphor "are emerging as a new wide color gamut solution."

The faster processors should also deliver a welcome upgrade from the Intel (INTC -1.79%) Haswell processors found inside of the current iMac lineup. I believe that the 27-inch iMac models will move directly to Intel's soon-to-be-announced Skylake architecture, while the 21.5-inch model(s) could potentially move to Intel's Iris Pro-equipped Broadwell chips, since it is not clear if the Iris Pro variants of Intel's Skylake chips will be available this fall.

What about graphics?
In addition to the upgraded CPU, new 27-inch iMacs will likely include improved graphics processors. The standard (i.e. non-Retina 5K) 27-inch iMac model comes with an NVIDIA (NVDA 0.76%) GeForce GT 755M, while the Retina 5K models come with either an Advanced Micro Devices (AMD 0.69%) Radeon R9 M290 or, for the higher-end Retina 5K model, the Radeon R9 M290X.

Apple has seemingly been transitioning away from NVIDIA discrete graphics in its Mac products toward graphics from AMD. I expect that as Apple moves its 27-inch iMacs to Skylake processors, AMD will become the sole vendor of discrete graphics in those designs.

For the 21.5-inch iMac, Apple has three different tiers. The cheapest model (starting at $1099) uses essentially a MacBook Air-class processor with integrated Intel HD graphics. The middle model uses a faster processor with more cores and a higher-grade integrated graphics, and the highest-end one uses an NVIDIA GT 750M.

Trying to figure out what Apple will do with new 21.5-inch iMacs, should they arrive later this quarter, is a bit tricky.

If Intel has Skylake processors with Iris Pro available by the time Apple wants to roll-out new iMacs, then I'd expect the whole lineup will move to Skylake processors. If not, then I could see Apple moving to Broadwell-U for the lowest-end iMac, Broadwell with Iris Pro for the middle model, and Skylake paired with discrete graphics for the highest end model.

As with the 27-inch iMac models, Apple's recent choices of AMD discrete graphics for other iMac/MacBook Pro models suggests that the NVIDIA GT 750M will be replaced with a higher-performing graphics processor from AMD.

A solid upgrade coming for the iMac
With better internals, coupled with a "much better" display, the new iMacs should represent solid evolutions of the iMac lineup. I'm not expecting that customers will flood their nearest Apple stores in order to get ahold of these new Macs should they launch later this quarter as Kuo predicts. However, for customers who held off on buying new iMacs in anticipation of newer models, I think the new models will have been well worth the wait.