Tech problem - spikes of horrid FPS

[Rothom]

I run the game at it's lowest settings and it runs smooth 80% of the time. However, after playing for a bit I start to suffer bouts of horrid FPS (I've seen Power Point presentations move faster then the game)

 

Any suggestions on how to improve this? Buying a new system is out of the question, but upgrades to my current laptop may be doable.

 

I'm playing on a Gateway P-7805u with the following system specs:

 

 

Windows Windows Vista Home Premium Edition (64-bit) Service Pack 2 (Build 6002)

Internet Explorer 9.0.8112.16421

Memory (RAM) 4090 MB

CPU Info Intel® Core2 Duo CPU P8400 @ 2.26GHz

CPU Speed 1728.8 MHz

Sound Card Speakers (High Definition Audio

Display Adapters NVIDIA GeForce 9800M GTS | NVIDIA GeForce 9800M GTS | RDPDD Chained DD | RDP Encoder Mirror Driver

Monitors 1x; Generic PnP Monitor |

Screen Resolution 1920 X 1200 - 32 bit

Network Network Present

Network Adapters Marvell Yukon 88E8071 PCI-E Gigabit Ethernet Controller | Intel® WiFi Link 5100 AGN

 

 

Any help would be great. Thanks!