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Table of Contents
Grub Bootloader
Framebuffer VGA Code
Syntax
you are passing the hex or ascii formated number to your kernel in the /boot/grub/menu.lst or at startup by editing your config otf (will be vanished at reboot)
befor editing it looks something like this:
kernel /boot/vmlinuz-x.x.xx-xx root=/dev/sxx ro
after editing it should look something like this:
kernel /boot/vmlinuz-x.x.xx-xx root=/dev/sxx ro vga=xxxx
Framebuffer Codes (4:3)
| Colors | ( depth) | 640×480 | 800×600 | 1024×768 | 1280×1024 | 1600×1200 |
|---|---|---|---|---|---|---|
| decimal | ||||||
| 256 | ( 8 bit) | 769 | 771 | 773 | 775 | 796 |
| 32,768 | (15 bit) | 784 | 787 | 790 | 793 | 797 |
| 65,536 | (16 bit) | 785 | 788 | 791 | 794 | 798 |
| 16.8M | (24 bit) | 786 | 789 | 792 | 795 | 799 |
| hexadecimal | ||||||
| 256 | ( 8 bit) | 0x301 | 0x303 | 0x305 | 0x307 | 0x31C |
| 32,768 | (15 bit) | 0x310 | 0x313 | 0x316 | 0x319 | 0x31D |
| 65,536 | (16 bit) | 0x311 | 0x314 | 0x317 | 0x31A | 0x31E |
| 16.8M | (24 bit) | 0x312 | 0x315 | 0x318 | 0x31B | 0x31F |
Framebuffer Codes (16:10)
for resolutions like 1680×1050 which is non-std. run vbtest and add 512 to the number in the brackets like [353] for 1680×1050 (5:6:5) → 353+512=865 pass that to your kernel either in decimal (vga=865) or in hexadecimal (vga=0x361)
Hints
not all grafic cards do support frambuffer code settings, so dont drive yourself mad! test the codes before you write them into your menu.lst.
External Links
Grub2 Bootloader
Grub2 does count harddisks from 0 and partitions from 1!!! “root=(hd0,1)” is first harddisk's first partition
