This is happened this last weekend when I had to gracefully shut down the Myth system a couple times for guests.

Anyway, when I rebooted the system it hung at the "Storage, Network and Multimedia [OK]" line. It refused to progress though the rest of the boot sequence. I plugged a monitor in and got the same thing. Not until I unplugged the SVIDEO out cable and rebooted would it proceed as normal. This was a completely functional system up to this point. I have not tried another video card in the system yet.

Myth System:

FC3 with latest Myth version
Abit NFS v2 motherboard
AMD 2500+
Nvidia 5200 video card

Anyone have a clue what I can check to get this to boot again with a TV plugged in?