Boot menu only displayed over DVI and not HDMI

[f_benning]

I installed an ubuntu dual boot on my pc and could not access the boot menu to select between Ubuntu/Windows until I finally plugged an old monitor in, using a DVI cable. It appears that the Boot menu is only displayed over DVI and the HDMI provides no signal until the OS is booted. Since the new screen does not have a dvi port, this is an issue. This is explicitly NOT an issue with the os since every problem goes away once it is booted. I updated the Bios to F.45-05/22/2019, but there is still no option to select a display output. I also updated the ubuntu/linux grub, even though this was a fresh installation, just to be sure. 

Any help would be appreciated. 

[WAWood]

@f_benning 

When you say "boot menu", you mean the GRUB menu that lists Linux choices as well as Windows?

You have to be able to boot into Linux GRUB to display that menu, and if that's the menu, we can't help because HP does not supply any Linux drivers.

You would have to check on the Ubuntu Forums to see if they can point you to such drivers for Linux.

[f_benning]

The HP symbol which pops up before the menu (yes GRUB) shows up, is also only displayed via DVI. This was one of the reasons why I had the hunch to try the old monitor in the first place.

Someone has had a similar problem, where it only showed up via HDMI: https://askubuntu.com/questions/503707/how-to-choose-default-output-port-boot-screen-in-a-nvidia-car... , and in their case the Dell logo also only showed up via HDMI. So I doubt that linux would sometimes make GRUB only show up via DVI and then at other times only via HDMI. And the logo should still appear on both outputs then. But it doesn't. 

[WAWood]

@f_benning 

You make a good point -- in that since the HP logo comes from firmware programmed into the chip on the motherboard, its display should be driver-independent and it should show up on the display screen regardless of the video port used.

So, sorry, I have no explanation as to why that does not display when it should.

[frilly]

I think I had the same problem as you until today!

Background:

I have a HP Phoenix 1200 Desktop with a Debian / Windows 10 Dual Boot. I could not see the HP Logo or the Grub Screen when connected to a LG Screen (Pretty new and modern, Ultra HD and all that). Time would pass and it would go straight to Debian (Because I could not select anything in Grub as I could not see it)

I tried it on an older Screen, DVI on Desktop to VGA on then Screen and I could see the HP Logo and Grub!

Then I tried a different combination HDMI on Desktop to HDMI on the old screen and it also worked.

That made me realize that the issue were not the ports on the Desktop but the new LG Screen

Then I started lowering all configurations on my new LG Screen:

  1 - I tried HDMI to HDMI and I disabled "HDMI Ultra HD Deep Color" option on the Screen and it worked! I could see Grub on reboot.

  2 - I also tried DisplayPort to DisplayPort and I disabled the "DisplayPort 1,2" option on the Screen and it also worked!

My conclusion is that perhaps Grub is not Ready for newer resolution/versions of ports.

The only anoying thing now is to have to lower the quality of the screen to see Grub and then putting it back when I enter either Debian or Windows

I hope this helps! Perhaps Grub has an option for displaying on newer resolution/versions of ports...

[f_benning]

Interesting. My HDMI output is in fact also used by a fairly new LG screen. Although I thought I tried to use the hdmi output with the monitor which was working with the DVI connection and it also did not work. But maybe I should try that again.

I do not think that Grub is at fault though. Since the hp logo should be displayed as well, and that seems to be unrelated to Linux. It might be worthwhile to ask LG about it though.

[f_benning]

So I double checked (took me quite a while to actually do it). And apparently the hp logo is displayed over HDMI over the old display. So I guess it has something to do with the LG display