[gentoo-user] How to increase console (text) screen resolution

[Harry Putnam]

What is the simplest way to get a higher resolution screen when
booting gentoo into console mode?

I used to have something in /boot/grub/grub.conf that did that but I
have forgotten the full syntax.  My best guess is:
    [...] vga=0x31a video=vesafb:mtrr,ywrap
on kernel line.

With that in place, at bootup the terminal expands to a (quite a lot)
bigger size, but it's only momentary and then right back down to what
is I guess default.

So either I missed something in the kernel or that stanza is outdated
now.

Or maybe, FB doesn't work for vbox guest vm.

(ps I'm not interest in wasting huge amounts of time with the KMS
approach.)