"ATI Mobility radeon premium Graphics Card"
Which model ?
Have you patched the game ?
If you are using Anti-Aliasing or Ambient Occlusion turn them off.
Apparently the game is very poorly optimised for PC (yet another bad console port).
A lot of people experience dramatic frame rate drops in areas with a lot of activity.
These problems are supposed to have been addressed with patches, but if not,
making a couple of changes in the games configuration file may help -
- Go into the config file. Open it with notepad and change-
vsynchinterval=1 change it too 0 (This turns V-sync off. V-sync is not necessary with fps
below 60).
- Also change the line
lockto30=false too lockto60=true - ( this should lock in a maximum of 60 fps. You could
also try using lockto30=true)