FPS problems

I need some help any console commands that can help fps?
i have

Operating system:Windows (SP 3)

CPU type:Intel® Core™2 Quad CPU Q6600 @ 2.40GHz

CPU Speed (GHz):2.42

System memory (GB):3.248

Graphics card model:NVIDIA GeForce 9800 GTX

Hard disk free space (GB):432.691

my garrys mod resolution is 1024x768

i can only get around 70 fps as my max

Why? 70 is fine.

-dxlevel 81 turn off HDR.

Why do you care about only getting 70 fps? Do you have AA on or something?

even with 70 fps i skip alot and get alot of lagg and 70 is my max doesnt mean its a constant 70 fps at all times

anyone know a way to help