Just a bit of animation

3D modeling doesn't pay mind to DPI, DPI is post processing. I think that you're asking is how low my noise threshold is, how high my subdivs are, and how many passes I afford each frame.

Noise threshold is 0.06, subdivs is 8, and I'm using 3 passes

These settings determine how much detail the camera will capture and render upon completion of the render phase. For example, here's a screenshot of the renderer between the 2nd and 3rd pass:

 

Hmm, what software is that?

 

I use 3DS max, and the renderer is the built in MentalRay