In the Windows setting don't use SLEEP, use HIBERNATE.
It's confusing indeed: for the button sleep means what Windows calls hibernate. Sleep in Windows means something different.
http://www.howtogeek.com/102897/whats-the-difference-between-sleep-and-hibernate-in-windows/ tells the difference.
I have 64bit Windows 7 on my K55A Asus Notebook.
If I press the sleep button, then my laptop will easily save 95% of it's power up to 24 hours later.
-However, if I set my Windows setting to sleep after 30minutes, then it loses almost 100% of it's power simply overnight.
--How do I fix this?