Help needed with Darksiders 2

I am trying to play Darksiders 2 on my laptop. First 5 - 10 minutes it runs smoothly but then frame rate drops to the point it is impossible to play. It happens anywhere in the game even if the environment does not require intensive rendering. Any suggestions? Should I tweak something?

Here are the specs for my laptop:

Sony Vaio S series with 

- Intel i7-3520M 2.9 Ghz


- 8GB of RAM

- HD4000 integrated graphics card and GeForce GT 640M LE with 1GB memory.

Since it is a port from a console version, In-game video settings is next to none. I could not find config file either. The game uses GeForce for rendering, and I tried disabling all performance heavy processes from Nvidia control panel. The driver is up to date as well. However, nothing helped so far to resolve the issue.


Thanks in advance.