Windows 7 x32 I found that no matter what I did, the driver being used dated back to 2006. It would not update, in fact Windows appears to be preferring the old driver to the new. I eventually found a way to sort it.
The Device Manager contains 'ghost' drivers that need to be deleted (if you have the same problem as I). To see them requires setting a variable in the registry, restarting and then deleting the likely redundant drivers.
Open the Device Manager from the command line use devmgmt.msc There are other ways, but this is easiest to describe. Currently it shows only 'current' drivers.
Open the System Properties box. Via Command line use sysdm.cpl
** Be aware that playing with area of your computer can break it. Back away if you are at all unsure of this. **
Re-open the Device Manager, under view click Show Hidden Devices.
From here delete what you think are the problems then follow the advise you will have read elsewhere. On two seperate computers I have done this and found all I needed to do following this was download and install the standard google drivers as per user3079537's answer above. Good luck.
ref: http://www.petri.co.il/removing-old-drivers-from-vista-and-windows7.htm#