Click on the "Support" tab of this website, enter in your notebook model number (IE - G580...) into the search box and pick from suggested models that it shows. Once selected it will refresh the page with your drivers. Also, at the bottom of the page you will see a link to documentation and if clicked will transport you to the documentation for your notebook (service manual, maintenance manual, user guide) in PDF form.
I do not work for Lenovo, I only provide suggestions based on my personal willingness to help others. All advice and comments are based on my experience, and do not reflect Lenovo policy, terms or conditions.