# grub menu - blank screen

## Joseph_sys

When I boot my box I see BIOS message but next screen should show kernel selection, but my display goes blank (no picture)

I have only two selections (two kernels) so I just hit enter and the computer boots normally and picture shows up.

In grub.conf I don't have any special options:

kernel /boot/kernel-current root=/dev/sda3

Monitor is BenQ V2400WLast edited by Joseph_sys on Sun Dec 25, 2011 10:25 pm; edited 1 time in total

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## NeddySeagoon

Joseph_sys,

How many display devices do your have connected?

Is this a laptop?

Its some setting in your BIOS or the boot loader, since the kernel menu is displayed by the boot loader before any kernel is loaded.

Does the display go blank or does it go into a power saving mode?

If you wait for the boot loader time out does the boot sequence continue normally.

Post your boot loader setup please.

Thats /boot/grub/grub.conf  or /etc/lilo.conf  depending on your taste.

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## Joseph_sys

 *NeddySeagoon wrote:*   

> Joseph_sys,
> 
> How many display devices do your have connected?
> 
> Is this a laptop?
> ...

 

Thanks for helping hand.

The video card is Asus EAH6770 DC SL 2DI1GD5

Single monitor,  connected to it.

Monitor has VGA, HDMI and  DVI-D ports.

(VGA connection is working, DVI from video card to HDMI on the monitor is not working, have to investigate it)

At the moment I'm using standard VGA cable,  grub.conf

```
default 0

timeout 30

#splashimage=(hd0,0)/boot/grub/splash.xpm.gz

title Gentoo Current Kernel

root (hd0,0)

kernel /boot/kernel-current root=/dev/sda3

#initrd /boot/initramfs-genkernel-x86-2.6.24-gentoo-r5

title Gentoo Old Kernel

root (hd0,0)

kernel /boot/kernel-old root=/dev/sda3
```

When I had it connected to my NEC monitor the kernel menu was displaying OK.  When I switch to BenQ V2400W (wide screen) the boot loader menu does not show up but one I hit blindly "enter" selecting first kernel-current the display only shows up when it start loading the Gentoo rc-optoins, nothing before.

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## Hu

Are you using the same VGA cable for both the NEC monitor and the BenQ monitor?  I once saw a system that was determined to present BIOS/bootloader only on VGA.  Once Linux booted and initialized KMS, it probed the devices and recognized that displaying on DVI was the right thing to do, at which point the DVI-connected monitor would receive a signal and come out of powersaving mode.

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## Joseph_sys

 *Hu wrote:*   

> Are you using the same VGA cable for both the NEC monitor and the BenQ monitor?  I once saw a system that was determined to present BIOS/bootloader only on VGA.  Once Linux booted and initialized KMS, it probed the devices and recognized that displaying on DVI was the right thing to do, at which point the DVI-connected monitor would receive a signal and come out of powersaving mode.

 

I'm using VGA cable the same before, my DVI connection doesn't work even after the kernel starts.

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## NeddySeagoon

Joseph_sys,

It sounds like the grub menu is being displayed on the wrong display surface or that grub is generating a resolution your display does not like.

The latter is unlikly on two counts. grub only does 640x480 and you did not mention any 'input out of range' message from the display.

You have already commented out you splashimage line, which is good.

You did not mention if the display went into powersave mode, which would indicate that grub was driving another video output.

Your DVI output should have both digital and analogue outputs.  If you have a DVI to VGA adapter (provided with most video cards) you can see what comes up on the analogue pins on the DVI connector on the graphics card.

The right answer is nothing but its an easy check.

I've seen a few odd things with video cards too.  Assume nothing.

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## Joseph_sys

 *NeddySeagoon wrote:*   

> Joseph_sys,
> 
> It sounds like the grub menu is being displayed on the wrong display surface or that grub is generating a resolution your display does not like.
> 
> The latter is unlikly on two counts. grub only does 640x480 and you did not mention any 'input out of range' message from the display.
> ...

 

I don't know what is going on but it only display picture on D-sub (this is VGA connection, I think, DVI is blank no output signal is recognized by my monitor) I had a DVI working with this monitor with another computer so it must be the graphic card.

No I don't get any error message or anything as soon as the BIOS screen disappears and it is time to show grub config menu the screen goes blank until the the gentoo rc-scripts getting ready to load.

I don't even know where to start.

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## Joseph_sys

The strange part is that I plugged IN another (older PCI video card, VGA) and the screen went bank on Grub-Menu as well.

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## NeddySeagoon

Joseph_sys,

Rebuild grub and reinstall it to the MBR.

grub can behave oddly if its three parts get out of step.

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## Joseph_sys

I tried it, emerge grub

grub-install --no-floppy /dev/sda

Installed to (hd0) 

no errors reported.

But it still no Grub Menu at boot (just blank screen) :-/

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## Joseph_sys

Another interesting part is that I can not even enter BIOS setting screen when I hit "delete" button.

I just get a blank screen.  

Is it a problem with this video card?  

I had this BenQ V2400W connected to another box and everything was working OK.

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## Hu

It is possible that there is a problem with the video card, but I would still suspect bad behavior of the BIOS before I suspect that the video card is non-functional in pre-OS mode and suddenly starts working when Linux takes over.

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## jburns

Try removing the "#" from the #splashimage=(hd0,0)/boot/grub/splash.xpm.gz line

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## Joseph_sys

 *jburns wrote:*   

> Try removing the "#" from the #splashimage=(hd0,0)/boot/grub/splash.xpm.gz line

 

Thanks for the hint, yes it worked.  After BIOS screen flashes it goes blank for two seconds and the grub menu shows up.

That "splash" activate somehow something in the card  :Confused: 

The only thing I need to figure it out why my cable doesn't work. I'm using standard video cable but the card has interfaces:

D-Sub Output 

DVI Output : Yes x 1 , Yes x 1 (via HDMI to DVI adaptor x 1)

HDMI Output

The monitor has input: 

D-Sub,  DVI-D,  HDMI

My cable is: male DVI-D (single link) connector on one end and HDMI  on the other.

Connecting this cable to DVI on video card to HDMI on the monitor does not produce any picture.

Do I need HDMI to HDMI cable?

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## Joseph_sys

Though, there another strange thing about this Radeo card.  I CAN NOT enter BIOS menu.

When, the system boots and I don't touch any keys, the Grub menu show up with kernel option selection.

If I hit "delete" key to try to enter BIOS settings,  there is only blank screen.

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## NeddySeagoon

Joseph_sys,

I have a couple of laptops with partially dead nVidia GPUs that exhibit similar symptoms.

On power on, and every graphics mode change, the video comes up on the external interface only.

You have to cycle around the graphics outputs to get anything on the laptop screen.

Some graphics modes work better than others. In the grub screen, several columns of pixels are black, once you get to an image.

Only the vesa driver works nv and nvidia-drivers cause the system to crash - no surprising with a partially dead GPU.

I think a dead GPU is unlikely as you can produce identical symptoms with two different cards.

Single link DVI cables can support dispaly resolutions only up to a certain resolution (which I forget) but its at least 1920x1080 for 1080p images as HDMI is single link DVI-D with a different connecor on the end. I'm not sure what happens when you try to run a resolution that needs dual-link with only a single link cable.

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## NeddySeagoon

Joseph_sys,

I have a couple of laptops with partially dead nVidia GPUs that exhibit similar symptoms.

On power on, and every graphics mode change, the video comes up on the external interface only.

You have to cycle around the graphics outputs to get anything on the laptop screen.

Some graphics modes work better than others. In the grub screen, several columns of pixels are black, once you get to an image.

Only the vesa driver works nv and nvidia-drivers cause the system to crash - no surprising with a partially dead GPU.

I think a dead GPU is unlikely as you can produce identical symptoms with two different cards.

Single link DVI cables can support dispaly resolutions only up to a certain resolution (which I forget) but its at least 1920x1080 for 1080p images as HDMI is single link DVI-D with a different connecor on the end. I'm not sure what happens when you try to run a resolution that needs dual-link with only a single link cable.

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## Joseph_sys

This video card works OK on standard size monitor NEC it only have a problem with wide screen 24in monitor BenQ V2400W 

Though, this monitor displays BIOS setting OK when I connect my other box with GeForce 8600 card.

It seems as if the card had a problem with 640x480 display that standard BIOS is using.

I don't know who to blame Video Card or the monitor :-/ or has MotherBoard something to do with it?

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## Spidey

Are you keepking unused cables connected to the video card? I've seen videocards chosing to output to an unconnected cable when you have multiple cables attached, even if only one of the cables is actually connected to a monitor.

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## Joseph_sys

 *Spidey wrote:*   

> Are you keepking unused cables connected to the video card? I've seen videocards chosing to output to an unconnected cable when you have multiple cables attached, even if only one of the cables is actually connected to a monitor.

 

No, only one cable is connected at each point in time to monitor and Video card.

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## Joseph_sys

I just bought HDMI to HDMI cable, connected to the video card and no picture at all.

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