I've a Sony Vaio VPCS12L9E with Nvidia GeForce310M with OpenSuse 11.4 64bit.
I'm using lastest Nvidia drivers (x86_64-260.19.44) and when I switch to any of virtual console (ALT-CTRL-Fn) I get black screens.
The console is present because I can login and executing commands (blind login), and by switching ALT-F7 I can return in graphical mode.
I had the same problem also with previous driver versions with OpenSuse 11.3.
I've tried to use vga=normal as boot option in grub and also NVreg_UseVBios=0 as nvidia module parameter but they didn't help.
I've tried to follow this thread
Any suggestion to solve such very annoying issue?