Problem with DLL

[Igor_AMD]

When I start the game,my computer show dialog box with this "D3DX9_31.DLL not found,Direct 3d is not avaible" now game sart normali,but grafics is not good. on testing program like fraps i can get only 2 fps. Grafics card is good ATI 9600 Pro.I have athlon 64 and 1 GB of ram.
Please help