Problem: You have more than one monitor attached to the system, and the console is not set to the intended monitor.
If you have more than one monitor attached to the system, OpenBoot always assigns the console to the frame buffer specified by the output-device NVRAM parameter. The default value of output-device is screen, which is an alias for one of the frame buffers found by the firmware.
A common way to change this default is to change output-device to the appropriate frame buffer:
ok nvalias myscreen /sbus/cgsix ok setenv output-device myscreen ok reset-all
Another way of setting the console to a specific monitor is to change the sbus-probe-list NVRAM parameter.
ok show sbus-probe-list ( Display the current and default values)
If the frame buffer that you are choosing as the console is in slot 2, change sbus-probe-list to probe slot 2 first:
ok setenv sbus-probe-list 2013 ok reset-all
If a non-SBus frame buffer is installed, this second method may not work.