I installed Boot Camp on my Mac, then Windows 7 and the specific Windows drivers from the Mac OS X installation DVD.
On the Windows side, how can I know which version of the Boot Camp driver I am running?
Right click on the BootCamp icon in the TaskBar, then choose "About BootCamp".
BTW: what type of Mac do you have and how old is it?
Some models are not supported:
Are you sure you're using the latest drivers? I would recommend running the Apple Software Update to make sure you do.