it in the mb chipset driver.
if you have an intel mb it the intel chipset driver.
with amd there a few drivers run cpu-z and look at the chipset. write the number of the chipset then download the newest drivers the reboot.
i found this link: http://www.drivermax.com/driver/update/Chipset/Intel/In...
and it solved my problem about this sm bus controller driver problem.
you have to install DriverMax.
then check for driver updates.
it will show you all drivers that are not updated then you can click the update button corresponding it.
me i just updated my sm bus controller driver for its the only one that has the exclamation mark on it.
meaning there is no driver installed in it.
after it finished updating just click install and it will install automatically.
after installing you can check on your device manager and you'll not see the sm bus controller there anymore.
meaning the driver is already installed....
hope this help....