I have a i5 3470, 8gb ram 1333mhz, ssd 120gb, gtx 960 2gb.

I play at 1680x1050, and i wonder if i can run the witcher 3 at ultra, or somwthing close to it, without hairworks min 30 fps.
And do you know if overclocking the gpu will give a good performance boost?

Thanks for the help, i really want to play this game when i finish my university exams!!!!

Considering the graphics card, CPU and RAM you have, you should be no problem using Ultra considering the resolution you're playing at - just make sure you download the latest drivers before playing.

You should consider reducing some of the less important optical features to smothen things up.
A lot of the features really have very little impact on the overall experience.

I've set all the postprocessing options on and ambient occlusion on SSAO. Textures on High, shadows as well, grass (density and distance) both on medium, population density, terrain quality, also on medium, and water on low. And I get constant 30 fps, stable, never a single drop (rarely got 29 or 28). I'm playing with a R7 260x and a FX8350, try reducing one of these options and you'll notice an improvement I'm sure, for instance grass distance consumes a whole lot and you barely notice it at all, above medium that is.

I am playing on i5, 8GB ram, 960 OC and I have no problems at all. I have set pop density to medium, everything else to high, water, terrain, textures to ultra and HairWorks OFF. ~30 FPS without a single jam. Postprocessing high.

Just play with your settings, you will find a balance.

Roughly the same as I have but with 16 gig ram overclocked to 1666 (profile 1) in your bios, and This game runs and looks lovely, with no issues. (NO hairworks)

you can easily run it.
From what i have experienced the game is very well programmed in that regard, especially when compared to the witcher 3.
It really shows that they delayed it 2 times.
Compared to other releases it has basically no major bugs.
(Sure some people have issues but nothing major that can be reproduced by anyone)