I have a ROG Crosshair VII Hero MB with a 2700X processor, a Sandisk Extreme Pro for a boot drive and a Samsung EVO 970 M.2 drive in the lower M.2 slot. I am using the Microsoft driver for the 970 until Samsung/Microsoft resolve the version 3 driver problem. W10 is running the latest 1809 version.

I have two EVGA 1070 SC video cards installed in the system using the 2-way bridge that came with the MB. The Standard Monitor is connected via an HDMI cable. Based on another thread in this forum I tried re-installing the latest Nvidia drivers but under the Control Panel Nvidia still does not recognize that I have two cards installed. SLI does not appear as an option.

I have a similar configuration running on an ASRock Z97 Extreme6 MB with a 4790K processor and everything just worked as advertised. However, it's using a HD Monitor connected via the Display Port.

Help is needed to determine what I'm doing wrong or not doing to get SLI working on the Hero VII system.

Problem solved!! Re-seated the second 1070 and all is well. My screwup.