# Problem with UEFI-Framebuffer

## GOS

Hello,

the problem I have is about the UEFI-Framebuffer. 

Today I installed my System from a stage4-archive. After some hours I got it and now it works well in UEFI-Mode. But the framebuffer does not. I cannot change the resolution of the framebuffer. So I have to work with a 800x600 console. (But X works proper with 1280x1024!)

Entries in /etc/default/grub (GRUB_GFXPAYLOAD_LINUX=...) or in /etc/grub.d/40_custom (video=efifb vga=795) doesn't changed this. 

My Motherboard is an P8P67-M and the grafic-card is a Nvidia with the newest nvidia-drivers. 

Any ideas?

Best Regards

GOS

PS: Excuse my english

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## srs5694

Some suggestions:

Since you seem to be concerned with X's resolution, try using a driver for your actual video card in X, rather than using the framebuffer driver. This will almost certainly produce better performance, too. You may need to fiddle with your kernel's video drivers, though. Unfortunately, this has gotten trickier to get right in recent years, since X drivers now depend more on kernel drivers to work.

Try including a framebuffer driver for your actual video card in the kernel. This may override the EFI framebuffer device and enable you to switch resolutions.

Try using rEFInd rather than GRUB to boot Linux. The refind.conf configuration file includes an option called "resolution" that you can use to set the video mode. This might work where GRUB's setting for the resolution is failing.

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## GOS

Thanks for your answer,

I have a kind of solution for my problem. 

Uvesafb seems to work proper. I disabled vesafb an efifb in the kernel and activated uvesafb according to the Gentoo-Wiki. Then the modes one finds in /sys/class/graphics/fb0 with a preceeding V work proper. 

So uvesafb together with nvidia-drivers for X works good.

But nontheless I wonder that efifb doesn't work proper / no other resolution than 800x600 is adjustable.

Best regards

GOS

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## srs5694

 *GOS wrote:*   

> But nontheless I wonder that efifb doesn't work proper / no other resolution than 800x600 is adjustable.

 

The default resolution with many EFI computers is 800x600, at least when using VGA. (With DVI or HDMI, the monitor resolution is sometimes the default -- but not always.) Most computers also support 1024x768, and sometimes other resolutions. Setting an unsupported resolution won't work. I don't know if there's a way to determine what resolutions are supported in GRUB. In rEFInd, if you set an unsupported resolution, the program pauses to give you a list of the supported resolutions, so you could try that (even by installing to a USB flash drive if you don't want to use rEFInd permanently).

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## GOS

Thanks for your answer,

but it is no Problem to set the resolution in Grub to e.g. 1280x1024, but if Grub starts the Linux-Kernel the resolution swtiches back to 800x600. To see what resolutions are supported is not a problem. They are listed in /sys/class/graphics/fb0/modes. The only resolution listed there is 800x600.

But if efifb supports generally only 800x600 or probably also 1024x768 than I will use uvesafb from now on. 

Best regards 

GOS

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