Aurora R10, reserve power?

Just out of curiosity, does the Alienware Aurora R10 have a 30-second power reserve, or something like that?

I received a new UPS today, and just for my own amusement, I unplugged the Alienware while it was in Sleep state instead of powering it down first. To my surprise, it never lost power when I unplugged it from the regular wall outlet and plugged it into the UPS. Woke it up, and everything appeared normal.

If so, that is a pleasant surprise.