Is it possible to boost the GPU on Latitude E6420?

Hello!

Im here with a question as above is already asked; is it possible to boost the GPU in my case it is a Nvidia NVS4200M. The last owner has done it somehow but after I totally reset the computer it was worse in gaming. I know, I know, it's not made for gaming but i can still atleast play titles like GTA Vice City and SA. How to boost/overclock the gpu to make the laptop more powerful.