Thanks Tom, doesnt seem to make much difference. I see the 4K Cache is still experimental rather than default, are there any draw backs from using it?
This is a very strange scene that takes different amounts of RAM on different machines. I have three machines here with 128gb each. One takes 73GB when rendering the other 109GB and the third wont render it. Bizzare. I tried rendering it with DR and the host machine couldnt render it but the node could so the node contributed all the passes which I was surprised about. Great work from Corona DR that it can handle that situation. Like I mentioned, it makes a difference how long the scene has been opened for. If its just opened the scene like backburner and DR does, that is when the RAM usage is highest. My workstation only took 73GB but the scene had been open on that for a while so the RAM usage dropped.