Hello Phil, Welcome to the User Discussion Forums, PCG-281M is not a valid model number. it does say Model number right on the bottom there, but there are other labels on the computer. please follow this guide to find your model. http://esupport.sony.com/US/perl/suppor ... nfo_id=264
If you have Canadian, Latin American, or Brazilian model, at the above link switch country to the one of choice then it will direct you to your drivers page. http://esupport.sony.com/US/perl/suppor ... type_id=24 If you are unsure, or require assistance finding it, please contact support and an agent is ready to help.