Terrible performence , fps drops badly

[lampa]

Hello .

My performence in Cryostasis is horrible , I keep getting massive lag and fps drops . There are times when games run smoothly but there are time it doesn't . Here's my specs :

Processor: Intel(R) Pentium(R) 4 CPU 3.00GHz (2 CPUs)
Memory: 2046MB RAM
Card name: NVIDIA GeForce 9600 GSO

Is there any way to make my game run smoother ? I already LOWERED all the settings , turn off everything I can , and run the game in 800x600 . But sadly even then , the game is very laggy !