I get that strange problem with Vray rendering (3.63v here for Sketchup 2018). Whenever my rendering resolution exceeds 3000 px in any dimension rendering never gets past light cache phase, nor does it generate any light cache (I may get a few white dots) and then it crashes. If I have literally 2999 px there is no problem, the moment it goes to 3000 - it doesn’t work. Moreover it doesn’t matter how complex the model is.
I tried rendering with Brute Force and Irriadiance map, got the same problem - the rendering simply won’t start.
It doesn’t matter also if I use progressive rendering or not, if I use CPU only, GPU only or hybrid.
Do you know what may be the reason? It certianly isn’t my PC fault as it handles rendering in other renderers with a much higher resolutions.