Since the format and reinstall of the OS, have you had the opportunity to return to your laptop manufacturer's website to check for other driver updates, (bios, chipset, audio, lan, etc) especially keyboard and pointing devices, that you may need to support Windows 7. Most laptops have a keyboard combination involving a function key (Fn) to support the use of external monitors. Perhaps if you would list your particular manufacturer and model number, another member here may have some specific advice regarding that laptop.