It probably won't be in any BIOS updates as it's not a bug, It's working and that just might be the issue.
There may or may not be an easy way to shut it off. My net book has a system called eeEngine which controls power managment. In my case I can un install the software.
In Windows 7 there's performance settings, Vista must have something like that.
Go to RUN and type in "msconfig" look for it there under services or startup