The most common problem about installing Sony VAIO Z series Windows 7 drivers is incompatibility with the BIOS version. Don’t be too happy about finding a new driver online, as it could have conflicts with BIOS. Furthermore, you should check compatibility, as the wrong driver might not let you restart your computer even in Safe Mode. This means you will need a clean installation of Windows 7, causing you to lose important work and documents. Just be sure the downloaded driver is compatible with BIOS version and change it if necessary. Also, create a restore point before installing a new driver, as you can revert to it if something goes wrong.