Sleep to Hibernate -- Issue

I have my power options set as follows:


SLEEP
--Sleep after
-----On battery: 15 minutes
-----Plugged in: Never
--Allow hybrid sleep
-----On battery: Never
-----Plugged in: Never
--Hibernate after
-----On battery: 8 minutes
-----Plugged in: 360 minutes
--Allow wake timers
-----On Battery: Disable
-----Plugged in: Disable

POWER BUTTONS AND LID
--Lid close action
-----On battery: Sleep
-----Plugged in: Do nothing
--Power button action
-----On battery: Hibernate
-----Plugged in: Hibernate
--Sleep button action
-----On battery: Sleep
-----Plugged in: Sleep



Here is the issue I am experiencing:

When running Windows 7, I can close my laptop and it will sleep. 8 minutes later, it will kick up and go into hibernation, just like I want it to.

When running Windows 8 Consumer Preview, I can close my laptop and it will sleep. 8 minutes later, it will kick up and try to hibernate, but will fail. Thus, it will idle for a few minutes and go back to sleep. 8 minutes later, it will try to hibernate again, get stuck in idle, and go back to sleep. This is killing my battery. If I simply hit power button, it will hibernate. But I'm not sure why it's not going from sleep to hibernate properly.