Downloaded Windows 10 before checking Lenovo's support site...yes rookie mistake and should know better. Most of the Lenovo products do NOT support Windows 10 today and they DON'T recommend you upgrade to Windows 10. Did download Windows 10 onto existing 8.1 environment. Worked fine for an hour then the screens brightness decreased by 75% as the Intel HD Graphics card is not compatible with Windows 10. Recovered back to Windows 8.1 - will wait for Intel to catch-up with their graphics drivers before attempting another download. Overall first impressions of Windows 10 - looked good. No more IE have MS Edge now for web browsing.