Attached Link: http://www.renderosity.com/messages.ez?ForumID=12356&Form.ShowMessage=2356407

Leave texture filtering off. It does not improve quality - quite the opposite. Instead, lower the shading rate or the Max. texture size.

Larger Max. Texture size will not necessarily lead to a sharper render. Smaller may be better. (See link for the explanation.)

Lighting can make a big difference. Larger shadow maps will produce a better quality render. But you will take a memory hit.

There are no "ideal settings" for every render. It depends on what kind of image it is, what size, how it's lit, what kind of textures and models are used, etc. That's why you should set your render options by hand. If you aren't using any displacement maps, you don't need "use displacement." You do not need texture filtering in the vast majority of cases, but it triples your memory use, so leave it off. The best Max. texture size depends partly on the size of the image you are rendering. The Gaussian filter makes things look a bit blurry if set too high, but can soften dynamic hair so it looks more natural. Etc.