Lenovo G565 model 20071 Unknown device

Problem: There is unknown driver although all drivers were installed from Lenovo web page

Right click directs to ACPI as property for unknown driver.
Solution is here:
http://forums.lenovo.com/t5/Lenovo-3000-and-Essential/ACPI-VPC2004-Unknown-Device-Lenovo-g560-windows-7-pro-x64/td-p/205909

Unknown driver was actually utility - "Energy management".