PCSX2 runs slow on my laptop

So I got this laptop and installed PCSX2 in it. After I started playing Mana Khemia 2, some parts are usually slow like after entering the Old Quarry the FPS suddenly drops to like 30-40. Other than that and excluding some other parts like the student affairs, it's usually at 60 FPS.
It's a Compaq Presario CQ40 Notebook PC
Windows 7 Ultimate
Intel Core Duo CPU T6600 
2.20GHz
4GB RAM