Jagged edges on geometry in IRAY render?

Flortale

Here is the geometry of the those two blocks.

I even tried putting a smoothing modifier, but it didn't help.

BeeMKay

Try to increase the subdivision of the problematic elements in the Parameter Tab. If you start seeing polygons in the render (that's also true for human and clothing, if you start seeing jagged edges), it is usually a problem of not enough geometry for Iray to work with.

In the ParameterTab, make sure that you've switched from "Base" resolution to "High Resolution" before you increase the subdivision render value.

Petercat

You can also check the Pixel Filter Radius in the Editor in the Render tab. Default is 1.5, see what yours is set to.
(I use .75 for sharpness, to reduce the jaggies try a higher number like 2.0)

This is a problem with having a geometric pattern of pixels, like in a digital camera, rather than a random pattern like in film.

Anki

BeeMKay said:

Try to increase the subdivision of the problematic elements in the Parameter Tab. If you start seeing polygons in the render (that's also true for human and clothing, if you start seeing jagged edges), it is usually a problem of not enough geometry for Iray to work with.

In the ParameterTab, make sure that you've switched from "Base" resolution to "High Resolution" before you increase the subdivision render value.

Since 4.12, I'm getting jagged edges on my render (gen8). I'm trying to set resolution level to high in the parameters pane, but it just shows up blank. If I set it to base, it stays on base. I get bigger jaggies with base settings, so my issue must be relative to this setting. Why is high resolution not working ? 

EDIT : Nevermind I got it to work. Had to set it to subdivision level 3 (max) to completely remove the jaggies. I don't understand why this happens with 4.12, but never happened with 4.11.