[INFO] SD 11 Won't boot without monitor

I need to boot my PC without monitor (using the graphic card TV-OUT)
and I don't know how. If I plug only TV to the PC I've a boot failure:
nothing "beep", nothing on TV. If I connect the monitor after the PC
power on I can see on it the Video Card information (manufacture, video
bios version, ecc, all informations that normally come before POST). Is
a M/B problem or a VGA BIOS problem? (I've a Nvidia GeForce2 GTS with
TV-Out).

There is an option in M/B bios to ignore errors in the boot? I heard
about "Halt on....." item, but I can't find in NC611 Bios.

Thanks.