Download aplikasi penjualan berbasis web. Original Drivers and Applications for VPCS1 Series (Windows 7 64-Bit) To install VAIO Update (Windows 7 64bit).

I too own that same laptop model and went through the exact same problem as you did (brightness stuck at low) when upgrading to win8, on the sony website I found that this laptop model will not support windows 8 (which is a shame because everything else works but the brightness. Looks like the only options left are to reinstall win7 or go shopping for a new win8 laptop or if your feel that you can live with a dim screen you can keep things as they are, the choice is yours, Good Luck.