Computer won't boot if only displayport is in the GPU without HDMI; issue doesn't occur on older GPU

[Lohse]

Recently received my Asus Strix 3080Ti from Overclockers, and I've run into a small problem. Title says it all, for the most part?

If I have the GPU plugged in to my two monitors the way I'd ideally like, it doesn't boot. Not even getting to BIOS. Power On Self Test passes but nothing from there. That's one Displayport out from the GPU to the DisplayPort in on my monitor (Acer VG271UP), and a displayport out on my GPU with a HDMI converter to a HDMI cable to my second screen, a small repurposed Logik TV.

However, if I additionally plug in a HDMI from the HDMI out of the GPU to the HDMI in on the Acer, it boots. Acer auto-switches to the HDMI in for the bios screen, then back to DisplayPort once Windows boots. It's not that the presence of DP is inherently causing the issue, it's seemingly the lack of HDMI.

After a quick google of issues like this people blame the cheap DP cables, they 'provide power' to the computer when they should only do it to the monitor or somesuch...but the weird thing is that this behaviour didn't happen on my old Zotac GTX 1660. That was just plugged in from Displayport to the monitor and DP->HDMI converter to the Logik TV, same screens, same components aside from GPU, the same setup in the first paragraph of this post.

I've updated nvidia drivers on the 3080Ti and assigned screens, but unplugging the HDMI results in the same no-boot behaviour.

Any suggestions? Is it really just down to the DP cables? It's perfectly usable but is there anything to be concerned about if I keep doing it this way?

 

[JohnG7]

https://www.nvidia.com/en-us/drivers/nv-uefi-update-x64/

 

[Lohse]

https://www.nvidia.com/en-us/drivers/nv-uefi-update-x64/

Thank you for the link, but the installer says the update isn't necessary for the GPU once I hit proceed. Chances are it really is the cables themselves in question, then.

 

[LordBlood]

I had the same issue and it was the cable. It passes 5v back to the graphics card which causes boot up issues. I changed it and never happened again.

 

[Lohse]

I might have to do some testing then, but it's quite curious that seemingly even the cable that came supplied with my monitor does it (unless I just didn't test it with only that one in, and also weird that it doesn't happen with the 1660 and only happens when the HDMI is not plugged in. Like, to clarify, the only difference between 'not booting' and 'booting' is 'plugging the HDMI in'. Both the DPs are in in both scenarios.

Time to pick up a pair of certified cables and see?

 

[Purgatory]

I might have to do some testing then, but it's quite curious that seemingly even the cable that came supplied with my monitor does it (unless I just didn't test it with only that one in, and also weird that it doesn't happen with the 1660 and only happens when the HDMI is not plugged in. Like, to clarify, the only difference between 'not booting' and 'booting' is 'plugging the HDMI in'. Both the DPs are in in both scenarios.

Time to pick up a pair of certified cables and see?

Have you updated your motherboard BIOS and checked if the monitors also have firmware updates for them ? Also if your monitors have any ECO mode set while they are in sleep mode then that can cause issues too. One test for that is to turn the monitors on before turning the computer on (making sure they are not in sleep mode or deep sleep mode) to check for that bug.

 

[rare]

I had the same issue and it was the cable. It passes 5v back to the graphics card which causes boot up issues. I changed it and never happened again.

I’ve seen this problem lots of times. Out of spec DP cables. I sold a 6800XT on the forum and me and the buyer were trying to work out for ages why he couldn’t get it to work. Was the cable.