First of all I need to apologize for my English if I am not enough to tell my condition; but I will try to do my best.

My HDD broke down and I got a new HDD. My friend helped me to install Windows 7 and my computer's drivers, but I think we missed one driver.

I could not find driver that I want because I do not know its name.

For example if you push 'Caps Lock' button in the screen there is a image pops up says that whether Caps Lock is open or not. Likewise for example if I use 'Volume Up' or 'Volume Down' buttons on keyboard also there is a image pops up for informing you about volume's state.

After new HDD and installing essential drivers I could not find one driver that I told. 

I hope my English was enough to tell my condition and I am waiting for help to find that driver.

Thank you.