I play COD4 on my laptop and I have a lag problem. My laptop has 3G RAM so it isn't terrible in that area. I turn off my anti-virus software while gaming, and all of the graphics settings in COD4 are turned as low as possible as far as I can tell. So why am I still lagging?

Computer specs:
CPU -- AMD Turion Dual-Core RM-70
CPU Speed -- 2.00 GHz
RAM -- 3G
OS -- Vista
Video Card -- NVIDIA GeForce 8200M G (which has 1.4GB video RAM, vertex and pixel shader vers. 4.0)

Internet specs:
Connection -- Comcast cable

Router used -- WGR614 v7

Thnx for your time,

-Brett