Screen resolution for Grub menu?

[Snowhog]

Okay, what file do I look at to find the screen resolution being used by Grub (when the Grub boot menu is displayed)? I'm making my own splash images - 640x480 - but the image is being "stretched", so the resolution being used is something else.

[Qqmike]

Re: Screen resolution for Grub menu?

You might see if dibl's how-to source mentions this or has a link that applies.
("...the authoritative source of information on the subject:
http://ruslug.rutgers.edu/~mcgrof/grub-images/ ")

[Snowhog]

Re: Screen resolution for Grub menu?

Thanks Mike, but that link doesn't address the question. Before the system executes startx to load the KDE environments desktop settings, is it KDM that is 'running the show' and controlling screen settings?

[Qqmike]

Re: Screen resolution for Grub menu?

I just now noticed your reply to my reply.
Your Q: I don't know--have not thought about this at all.
You could download the GRUB source code files and perhaps get at it there (maybe in some of the notes, comments, readme files, some of the more obvious code lines). Sorry. You can also post a question to the Super Grub Disk mail list about it.
EDIT added: One other idea, which you've probably tried, but the sites that tell you how to make your own splash images should address this (directly or indirectly). I mean, I would guess lots of folks are doing this who have no clue about KDM, MDK, DMK, or GRUB's interfaces!

[MoonRise]

Re: Screen resolution for Grub menu?

KGrubeditor states that the image needs to be 640x480 with a 14 BIT color palette.

Mine appears stretched as well, but it is also on a wide screen monitor. The monitor itself displays 640x480 when GRUB shows.

[Snowhog]

Re: Screen resolution for Grub menu?

I'm wondering if the splash image file really needs to be sized at 640x480. Given that when it's displayed by GRUB, on a screen that is obviously displaying a resolution greater than this, makes me question the stated size requirement. Of course, I'll just test my theory by creating an image file bigger than the stated size and see what happens.

[Qqmike]

Re: Screen resolution for Grub menu?

I recall now what MoonRise said (the image needs to be 640x480 with a 14 BIT color palette) -- Maybe that summarizes all the end result that the higher-level user needs to know ( ? ).

[MoonRise]

Re: Screen resolution for Grub menu?

Everything I just looked through states that GRUB can't display higher than that because it's based on what the BIOS is set to show. Sure enough when I boot (luckily my monitor displays briefly the current res.) the BIOS splash and the GRUB all stay the same. It doesn't change until it starts to load the kernel and showing the Boot Splash. I think you can mod the boot splash res. with the vga= statement for the linux kernel entry in GRUB.

[Qqmike]

Re: Screen resolution for Grub menu?

Gosh MoonRise, you are doing a good job helping us old guys (me) recall stuff -- Yes, BIOS is the limiting factor in the chain. (Hell, I was the last to jump into the splash image stuff, and now you see why ); and with all my experiments, I've lost track of my splash images ...

[MoonRise]

Re: Screen resolution for Grub menu?

I only remembered all that because it hasn't been that long since I tackled the GRUB splash issue. Still had my notes!

[Snowhog]

Re: Screen resolution for Grub menu?

Okay, test completed. Created a splashimage of size 1024x768. Grub didn't like it - the boot menu displayed, but the image was not -- completely. Grub attempted to display something but it wasn't the image. So, I guess 640x480 is a strict limit for Grub. Oh well.

[Qqmike]

Re: Screen resolution for Grub menu?

I do also recall that now in my experiments -- above 640x480 I didn't get any picture, nada.

[MoonRise]

Re: Screen resolution for Grub menu?

Nope. Doesn't like that. I also hate the 14 bit color pallet. Very limiting. I don't mind the 640x480, but that grainy 14 color is the pits unless you use a "Logo" style approach. I read elsewhere that a new version of GRUB was being worked on that might address that but don't know if it is true or not. What version of GRUB doe the *buntus use?

[Qqmike]

Re: Screen resolution for Grub menu?

It's all version 0.97 -- so-called "GRUB Legacy."
vs GRUB2 (in development)

[dibl]

Re: Screen resolution for Grub menu?

I also hate the 14 bit color pallet. Very limiting.

640 x480, 14-color seems very limiting, indeed. I played with making splash screens using photos, and it seems they come out better if you start with one that doesn't have a huge amount of color variation in it. I made a decent one with a winter shot of my street with a lot of snow - even though it was a color shot, it was all very subdued and came out looking reasonable in Grub. Also old monochrome photos (think Ansel Adams or Civil War portraits) come out pretty good when converted to 14-color. But forget about Easter Eggs!