Light cache only

Is there a way to get rid of brute force and use light cache only for gi?
i have two 2080 tis, one 1080 ti and a threadripper 2950x and my interiors are still too slow to render… I need to speed things up somehow.

Isn’t it just one or the other? I see one GI solution and it is either LC or BF.

I’m pretty sure primary is always brute force and we choose secondary. That’s what I read somewhere anyway.

Yep, it’s in the Docs:
The primary GI engine is always set to Brute Force

Light cache isn’t high enough quality for the primary bounce unless you increase retrace threshold and all that does is add in more brute force calculations. For an example, do a cpu render with light cache for primary and secondary and see what you think!

I see. What about IM by the way? It’s not available in gpu mode… I wonder why .irradeance map is capable of good quality for primary, right?