If you’re used to running Framebuffer for higher resolution consoles within Linux console, then you’ll be used to the vga=xxx switch on your bootloader.  As this takes a three letter code for various resolutions, some may use vga=791 for example – but what if you want a different resolution?  You need a different code, which are below:

     +-------------------------------------------------+
          | 640x480    800x600    1024x768   1280x1024
      ----+--------------------------------------------
      256 | 0x301=769  0x303=771  0x305=773   0x307=775
      32K | 0x310=784  0x313=787  0x316=790   0x319=793
      64K | 0x311=785  0x314=788  0x317=791   0x31A=794
      16M | 0x312=786  0x315=789  0x318=792   0x31B=795
     +-------------------------------------------------+

So, for example, if you want 1280×1024 at 16M colours, you’d use vga=795… or for 800×600 at 64k colours, you’d use vga=788 and so on.