Hi ILIE2000,
If there are no 64 Bit drivers available from Sony for the Nvidia chip for your model you will need to install drivers released directly by Nvidia. To do this it will be necessary to use a modified INF file for the system to allow installation.
Have a look at the following link and read the quick start guide towards the bottom of the page on the right hand side.
http://www.laptopvideo2go.com/
Installing drivers that have not been approved or tested by Sony is of course at your own risk.
Rich