It all depends on the components being used, such as the GPU
At the risk of self-incrimination

, I've "toyed" with custom built "Hackint0sh" systems. Primarily for maintaining a lead in a quickly evolving technological world as it's a challenge which requires much research. Knowing the proper boards, GPU's, WiFi+BTLE Broadcom's combo PCIe cards (which we began using late 2012, moving from separate WiFi and BT chips to a single WiFi ac + BTLE 4.x that unfortunately resulted in many having wifi and BT connectivity issues since 10.8 yet performed perfectly running Windows on the same hardware, thankfully 10.12 addressed the kext issue), and much more. Contrary to earlier OS X releases, it seems 10.12 Sierra has become the "easiest" Apple OS to install on non-Apple systems, on par with Snow Leopard which begs the question"why?".
On topic
Skylake-X and Kaby-X
Intel will be ditching the E and K nomenclature in succeeding the Broadwell-E chips. New Mac's have been in a holding pattern primarily due to Intel's shift from their "tick tock" model with the introduction of "X" versions of Skylake and Kaby Lake processors in early June. Unbeknownst to many, Intel has been working with us on first access to early production lines of Skylake and Kaby Lake processors, not unprecedented for Apple and Intel. Unfortunately, constant delays meant benched Mac's. The primary interest is Thunderbolt 3, improved integrated graphics and 4K support, Xeon E3-1500 v5 server chips (Mac Pro), and more. Kaby Lake was on track for a Q2 2016 launch, thus we held back. With the news of "X" variants in June promised no later than Q3, we held back.
In August, Intel announced Skylake-X and Kaby Lake-X would be shelved until late 2017. From what we heard through the pipeline, Cook was pissed. Some close to the situation claimed he channeled Jobs' level of anger as Apple began seeing declines waiting for Intel to get it together. Rumor mills suggest we may begin producing processors as Apple is focusing on in-house production for crucial components (CPU's) while introducing high-end dedicated GPU display components with new production lines.
Time will tell. For the moment, there's no question Skylake will be the processor for the newly released portables. Intel announced 7th-generaton Kaby Lake availability in September, yet it was too late for inclusion in a long overdue Mac line update. iMac, Mac Pro, and displays will be delayed due to a shift towards new dedicated GPU options to improve 4K+ support, new displays, and finally delivering on professional level systems.