White screen on startup

Mid-2009 MacBook Pro Unibody

This happened suddenly after a restart. When I power on, I get the POST check chime, then a blank white screen & no advancement.

I pulled the hard-drive, (250GB SSD), and put it in a USB enclosure and I can boot properly via USB, so drive is fine. When I replace it, I get the same results.

I am also unable to use any boot prompts when the hard drive is installed internally. I've reset PRAM and repaired Permissions on the disk, but no change.