Just choose one (or more) locations to download webcam driver file. Download webcam camera driver for windows 7 and windows 8 from here.
Also you can try other ways to fix webcam problems, so see more guides to help you
Webcam driver is very important to be installed
Without a proper driver, your webcam camera cannot record movies with sound of course.
Compatible with :
Windows 7 32 bits - Lenovo G505 - NO
Windows 7 64 bits - Lenovo G505 - Passed
Windows 8 32 bits - Lenovo G505 - NOT SURE
Windows 8 32 bits - Lenovo G505 - Passed