Hi Relenting and Welcome to ROG
There are a number of troubleshooting points to check.
Check if your on-board HDMI and display ports are working. (without the GPUs installed)
Make sure the graphics cards are seating correctly. ( I have heard of a situation where the standoffs were too short,relative to the expansion card mounting brackets)
If you don't have the latest Bios, upgrade and clear your CMOS. You can update without video, using the flashback port on your IO panel. If unsure how, just ask.
Remove all unnecessary peripheral devices initially, till the GPU issue is sorted, then add them back one at a time.
Ensure all drivers are up to date, if and when you can enter your OS.
Hope this helps and please report back.
We owe our existence to the scum of the earth, Cyanobacteria
My System Specs:
MB:ASUS ROG Crosshair VII Hero/WiFi GPU:EVGA GTX 1080 sc PSU:Corsair AX-1200i
CPU:AMD R7 2700X Cooler: Corsair Hydro H115i Case: Corsair Carbide 780t
Memory:G.Skill TridentZ F4-3200C14D-16GTZR SSD:Samsung 500GB 960 EVO M.2
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