Display Question

I recently had to have a new hard-drive installed on my laptop and I'm in the process of downloading all the drivers, but I'm having a few problems locating the driver responsible for "stand-by", the option to shut off the monitor and have the computer still running, and also when I turn down/up the volume or mute it, it used to be displayed on the screen and it no longer does that.  Any help would be greatly appreciated!!!