Fractal without subdividing again


I’ve tried searching for this but only found old tutorials for early blender.

When I subdivided an object I get the option to use the fractal tool. However I would like to use this without having to sudvidid again, is this possible?

I use subdivid on my whole plane, and after that I want to select an area to fractal, without subdividing that again. How would I do this?

Sorry for the noob question, but have tried without luck for a while now.

You can add and apply Displace modifier for that; use vertex groups to assign to some area only if needed.

Sorry, but how do I do that. I added the displace but I could not find fractal or get it to work at all, not the assigning of vertex groups either.

I’m new to blender, have only used 3ds max before. Is there some tutorial for doing just that?

Fractal subdivide (it’s available as an option on t-panel only while you are in object’s Subdividing process)
displaces mesh vertices from their positions. Same does Displace modifier based not on some random generated numbers but on texture you create. Bunch of options on modifier tab allow for further tweaking.
Only thing you need is subdivided mesh.