[DSFix configuration for optimal performance?]

The same question but to give more details:

 

 

am a little bit confused to what should be my optimal settings considering the resolution. My native resolution is 1400 x 900

My specs:

Proc: Amd phenom II X4 955

Ram: 8gb

graphic: HD6790

So my qestion is what values should I use in:

renderWidth
renderHeight

and

dofOverrideResolution

Also as per instructions I turned off AA and blur ingame, so does it matter what is my in game options resolution (set it at 1400×900 32)?