Ultra M.2 PCIe Gen 3 side effects?

Dirtydeedz wrote: Question: 1. Would a single Graphics card x16 become reduced to X8 using 1 or 2 of these Ultra M.2 Slots(x4)? 2. If running in x8 PCIe would the GPU take a performance hit? Currently, I'm using a 780 on a PCIe 2.0 x 16 slot which is the same thing. I'm looking real hard at the Asrock Extreme 7+ which offers 3 X Ultra M.2(PCIe x4) slots.

Z170 chipset boards, like the ASRock Z170 Extreme7+, are different in the way they allocate resources to the Ultra M.2 slots, compared to previous boards using the Z97 chipset that have an Ultra M.2 slot.

Intel improved the Z170 chipset to include PCIe 3.0 lanes. All recent earlier Intel chipsets used PCIe 2.0 lanes. Intel calls the Z170 chipset interface DMI3, which again is based on PCIe 3.0.

With the new Z170 chipset DMI3 interface, the 16 PCIe 3.0 lanes in the CPU are no longer shared between the PCIe 3.0 x16 slots and the Ultra M.2 slots. The Z170 chipset's DMI3 interface is used for the Ultra M.2 slots.

A video card used in a Z170 board will have all of the 16 PCIe 3.0 lanes from the CPU available, and will run at PCIe 3.0 x16 when one or more of the Ultra M.2 slots are in use. ASRock Z170 boards do not use any of the CPU's PCIe 3.0 lanes for the Ultra M.2 slots.

The only tradeoff with this configuration is the DMI3 resources in the Z170 chipset are shared between the Ultra M.2 slots and the SATA III ports. When one of the Ultra M.2 slots is in use, two of the SATA III ports will no longer be available.

From this article, it would appear that even if the GPU(NVidia) is running at X8 it doesn't matter.