Do you have the power connectors connected to the video card? Can you get into the BIOS at boot up?
i5 8600K
OC 5.0GHz
Noctua NH-U14S
Motherboard Gigabyte Z370-HD3
G.SKILL Ripjaws v 16GB F4-3200C14D-16GVK XMP Speed 3200 14-14-14-34
EVGA GeForce RTX 2070 XC ULTRA GAMING
ASUS VG279Q 27" 1920x1080p 144Hz IPS panel G-Sync compatible