missing sm bus driver

Hi,
I've bought a Toshiba L755D-128 laptop (AMD) with pre-installed Win7. My son deleted the OS, installed Ubuntu and upgraded Win7.
It seems to work but in Hardware management I have a warning that the SM bus driver is missing. Trying to search for and download these has not been successful.
Can anybody tell me which driver is required and where I might find it?

TIA

Richard

You need to install a chipset driver.

I wasn't able to find one for your model, but the package below might contain it:

driver

Thanks for your help. It seems that the value added file is not the one, but the Display file (from the same site) does contain the sm bus driver.

The error has now gone away and I am grateful for your assistance.