Computer won't boot with 2 monitors connected! HELP

[kb1997]

I've been having this problem for about a year now. When I built my PC, I only had one monitor and everything ran smoothly and fine but as soon as I added a second monitor there is a 50/50 chance that my PC will boot up with two monitors connected.

When I turn my PC on it will turn on but nothing will display on both monitors and I get a white Light (CPU) error code on my Asus mobo (strix 270-e). If I want to start my PC with two monitors I have to unplug one monitor, boot up, then plug in the second monitor and everything is fine. I use DP to DP and HDMI to HDMI so I know its not the cables.

Also, I originally had a GTX 1050ti and when I upgraded to two monitors the problem started happening. I assumed it was the GPU so I waited and then bought a GTX 1070ti a while later. Same problem is still happening so I know its not the GPU. I also tried moving the GPUs to different slots in the mobo and same problem so the slots are fine as well.

I have tried Uninstalling and reinstalling windows and reverting to default on my BIOS settings and nothing happens. I have also tried configuring multi displays in the BIOS and that didn't do anything either.

Any suggestions? Thanks for the help in advance.

 

[velocityg4]

Does it matter which monitor is plugged in? When booting with just one.

Have you updated your BIOS?

 

[kb1997]

Does it matter which monitor is plugged in? When booting with just one.

Have you updated your BIOS?

It doesn't matter which one is plugged in, I can boot up with one monitor connected through DP or HDMI just not both at the same time. I have already updated the bios to the latest version.