How to change linux text mode resolution? GRUB_GFXMODE didn't help

After I set GRUB_GFXMODE it affected GRUB menu and some of subsequent printouts, but in the middle of boot, text becomes very small again, and I still want to make resolution smaller. Where else the resolution is changing during boot? Any usage of fbmode reports unknown mode or invalid argument:

$ sudo fbset 1920x1200-32
Unknown video mode `1920x1200-32'

$ sudo fbset 1920x1200
Unknown video mode `1920x1200'

$ sudo fbset 640x480-60
ioctl FBIOPUT_VSCREENINFO: Invalid argument

$ sudo fbset 640x480
Unknown video mode `640x480'

$ sudo fbset 640x480-8
Unknown video mode `640x480-8'

and so on.