I have a 4k x 2k screen resolution screen on a optimus/EFI system :
00:02.0 VGA compatible controller : Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06) (prog-if 00 [VGA controller]) 02:00.0 3D controller : NVIDIA Corporation GK107GLM [Quadro K1100M] [10de:0ff6] (rev ff) (prog-if ff)
I changed the resolution in /etc/default/grub like this :
# The resolution used on graphical terminal # note that you can use only modes which your graphic card supports via VBE # you can see them in real GRUB with the command `vbeinfo' GRUB_GFXMODE=1600x1200 # Uncomment to allow the kernel use the same resolution used by grub GRUB_GFXPAYLOAD_LINUX=keep
After beeing sure that this resolution match the card with :
sudo hwinfo --framebuffer 02: None 00.0: 11001 VESA Framebuffer [Created at bios.459] Hardware Class: framebuffer Model: "" Vendor: "" Device: "" SubVendor: "Intel(R) HSW Mobile/Desktop Graphics Chipset Accelerated VGA BIOS" SubDevice: Revision: "" Memory Size: 31 MB + 960 kB Memory Range: 0x80000000-0x81feffff (rw) Mode 0x033c: 1920x1440 (+1920), 8 bits Mode 0x034d: 1920x1440 (+3840), 16 bits Mode 0x035c: 1920x1440 (+7680), 24 bits Mode 0x033a: 1600x1200 (+1600), 8 bits Mode 0x034b: 1600x1200 (+3200), 16 bits Mode 0x035a: 1600x1200 (+6400), 24 bits Mode 0x0307: 1280x1024 (+1280), 8 bits Mode 0x031a: 1280x1024 (+2560), 16 bits Mode 0x031b: 1280x1024 (+5120), 24 bits Mode 0x0305: 1024x768 (+1024), 8 bits Mode 0x0317: 1024x768 (+2048), 16 bits Mode 0x0318: 1024x768 (+4096), 24 bits Mode 0x0312: 640x480 (+2560), 24 bits Mode 0x0314: 800x600 (+1600), 16 bits Mode 0x0315: 800x600 (+3200), 24 bits Mode 0x0301: 640x480 (+640), 8 bits Mode 0x0303: 800x600 (+832), 8 bits Mode 0x0311: 640x480 (+1280), 16 bits Mode 0x037d: 3840x2160 (+3840), 8 bits Mode 0x037e: 3840x2160 (+7680), 16 bits Mode 0x037f: 3840x2160 (+15360), 24 bits Config Status: cfg=new, avail=yes, need=no, active=unknown
In the first half of the boot the resolution is taken in account but it changes to the 4k x 2k during the second half. I have also tried to change the resolution in /etc/grub.d/00_header without success.
Thanks for any suggestion.