Visit the NVIDIA Driver Download page . For older cards like the GTX 400 series and newer, drivers version 326.29 and above introduced OpenGL 4.4 support.
This is a standard free tool used to check the exact version of OpenGL your hardware is currently running. opengl 4.4 download windows 7 64 bit
Another popular utility that lists the supported APIs for your specific graphics card. Visit the NVIDIA Driver Download page