Question PC acting weird with 2 monitors plugged in. (Rare issue, not like any other I can find.)

[Azeuz]

Hey, I was wondering if someone might know why this is happening, can't find any thread on it... (Sorry if this is the wrong section)

I have a newly built PC that works perfectly.... Except when I try to boot with multiple displays!

If I have 2 displays connected when booting it doesn't detect my any of my drives for some odd reason...

If I load optimized defaults in BIOS my HDD shows up with both screens attached but not my NVME drive.
(This removes my XMP profile and disables RESIZABLE BAR, I have not done any other tweaks)

If I unplug my second screen and boot, both my drives shows up and boots in to windows just fine.

I can then hotplug the screen to get both monitors running... Even with my tweaks enabled....

But I can't boot with both plugged in, any suggestions on what might cause this?

I have flashed the latest version of BIOS already...

Specs:
MOBO: B550 AORUS ELITE V2
CPU: AMD Ryzen 5 5600X
GPU: Sapphire Radeon RX 6700 XT NITRO + 12GB
RAM: 4x4GB Corsair Vengenace LPX DDR4 2666MHz
PSU: Corsair RM850x V3 850W
NVME: kingston sa2000m81000g - 1TB
HDD: st2000dm008-2fr102 - 2TB

 

[Vic 40]

Which M.2 slot do you use for the ssd?

 

[Azeuz]

Which M.2 slot do you use for the ssd?

M2A_CPU according to the manual

 

[Vic 40]

In the bios under the "Boot" tab is "Fast Boot" enabled or disabeld? If disabled what happens when you enable it?

You could try the other M.2 slot and see if that gives no problems.

Tried btw all video outputs on the gpu?

 

[Azeuz]

In the bios under the "Boot" tab is "Fast Boot" enabled or disabeld? If disabled what happens when you enable it?

You could try the other M.2 slot and see if that gives no problems.

Tried btw all video outputs on the gpu?

Will try changing ports first...
Fast Boot is disabled, is it recommended to be enabled?

 

[Azeuz]

In the bios under the "Boot" tab is "Fast Boot" enabled or disabeld? If disabled what happens when you enable it?

You could try the other M.2 slot and see if that gives no problems.

Tried btw all video outputs on the gpu?

Changing ports does not help...

 

[Vic 40]

Fast Boot is disabled, is it recommended to be enabled?

Not per se recommended, but worth a try at least for testing purposes. Saw alot of things that can be enabled/disabled in the bios when setting this one to enabled, so it has some influence besides as supposed making the system boot faster.

You use decent cables quality wise to connect to the monitors?

Looking at very specific parts right now, but can maybe be a motherboard fault as well.

 

[Azeuz]

Not per se recommended, but worth a try at least for testing purposes. Saw alot of things that can be enabled/disabled in the bios when setting this one to enabled, so it has some influence besides as supposed making the system boot faster.

You use decent cables quality wise to connect to the monitors?

Looking at very specific parts right now, but can maybe be a motherboard fault as well.

I do use a 5 meter "budget" DP 1.4 cable, didn't think it would have an impact but that may actually be it.
It is the only thing that has changed since this problem started...
I did run 2 monitors with 1.5 meter cables before without any problem...
The problem did not instantly start happening after the switch though...

But why would it make a difference and why would it cause this issue? 🤔

 

[Vic 40]

But why would it make a difference and why would it cause this issue? 🤔

View: https://www.youtube.com/watch?v=XFbJD6RE4EY

 

[Azeuz]

View: https://www.youtube.com/watch?v=XFbJD6RE4EY

Seems like this is the issue, trying with a new screen today to confirm.

 

[Vic 40]

Hope so, is an easy fix.