Acer Aspire V5-471PG BIOS key

Reference:
http://www.ehow.com/how_5809235_access-acer-aspire-bios.html

The BIOS key is really "F2". But why it doesn't work?
Because the shutdown of Windows 8 is not really shutdown. It should be "Hibernation" only.

How to really shutdown Windows 8?
Press "Shift" key when you shutdown PC. And the BIOS key "F2" should work at the next boot up.