PC won't boot unless one of my monitors is plugged into onboard graphics


Oct 2, 2014

Just finished building most of a new PC yesterday and decided to get it fired up and install windows, drivers etc. I'm encountering a very strange issue where my computer wont post unless I have one of my two monitors plugged into the motherboard graphics. If I don't, the white VGA status LED stays lit and both monitors stay black. If I leave a monitor plugged into onboard graphics and one plugged into my VGA, the computer boots fine and the graphics card is detected and fully operational. I ran FurMark and it is definitely using my graphics card.

Things I've tried so far with no luck:

  • ■ Swap monitors between ports (display port and HDMI, between both the card and the motherboard outputs)
    ■ Updated BIOS
    ■ Changed BIOS settings to make PCIE my primary graphics device (this setting does not appear to be saving for some reason)
    ■ Updated video drivers
    ■ Unseated and reseated the GPU. Made sure power cables were secure in the card and on the PSU.
My current specs are:

  • ■ ROG Strix Z390-E Gaming
    ■ i7 9700k
    ■ EVGA GTX 970 (2080 Ti is in the mail)
    ■ 16GB DDR4
    ■ Windows 10 Home
At the end of the day, it's not a super critical error since I can still boot and use my card, but it's rather annoying.