man STM_nocheckfb (Formats) - disable startup checks for framebuffer devices
NAME
STM_nocheckfb - disable startup checks for framebuffer devices
DESCRIPTION
If the file /etc/default/STM_nocheckfb exists at boot,
then SVGATextMode will be started even if a framebuffer device
has been reported by /proc/fb
The default behavior of a standard Debian installation is to
not run STM if framebuffer device(s) are active at boot.
This is probably what you want.
Override this only if you know what you are doing or are
desperate to find some way to crash your Debian system.
FILES
/etc/default/STM_nocheckfb
/etc/init.d/svgatextmode