Let's say you're at 23 HP and your CON score is 15. You're hit by Finger of Death cast by a 13th level Wizard, and as a result suffer 130 damage. Are you left at -107 HP, or does it simply drop you to -15 HP?
In 3.5e, I think it would have left you at -10 HP. However, I cannot for the life of me find anything in Pathfinder that says it wouldn't just leave you at -107 HP.