acerzr2 wrote:
I am also curious if the Intel 750 SSD will get its full bandwidth in the bottom slot.

This is the only thing ive found.

"The uppermost pair of full-length PCIe 3.0 slots (the grey-coloured ones) receive their lanes directly from the LGA 1151 CPU, so these are the ones that you will want to use for graphics cards or high-speed PCIe storage devices. x16/x0 and x8/x8 operation is supported, making 2-card SLI and CrossFire possible.

The lowermost full-length PCIe slot siphons four PCIe 3.0 lanes from the Z170 chipset’s plentiful stack. Thanks to the Z170 chipset’s healthy allocation of PCIe 3.0 lanes, this connector can be used simultaneously with a PCIe 3.0 x4 SSD in the M.2 slot. There’s nothing preventing the PCIe 3.0 x4-capable slot from housing an AMD GPU for a triple-card configuration, but the latency penalty would likely be significant.

A more sensible usage for the slot is as a home for PCIe SSDs such as the PCIe 3.0 x4 NVMe Intel SSD 750 drive. While this induces higher latency than the CPU-fed PCIe lanes, it also leaves those available exclusively to graphics cards. Two of the three open-ended PCIe 3.0 x1 connectors share bandwidth with the lowermost expansion slot and will force it into PCIe 3.0 x2 operation if all slots are utilised."

http://www.kitguru.net/components/motherboard/luke-hill/asus-maximus-viii-hero-z170-motherboard-revi...