Hi Hi,
I usually open my task manager and watch the Cpu percentage hit 100% and then stay there during a render but something has changed. I now see my RAM go up while its parsing but then the Cpu hit 100% on handover but after a few passes it sinks to around 7% - 9%. It used to sit at a constant 100% and the renders are MUUUCH slower.
Any Ideas out there?
Also 100% disk usage ;]
You sure you turned off bitmap paging? Thats a classic tell tale sign of it.
https://coronarenderer.freshdesk.com/support/solutions/articles/5000675862-you-have-3ds-max-bitmap-paging-enabled-this-is-known-to-drastically-reduce-performance-of-textures-w
Strange thing is if I hide my plants layers then it renders at 100%?
Paging is disabled though. Got super excited thinking it was the answer 
Any other suggestions?
Something is caching and reading from cache, that is obvious. Do you use a plugin? How did you scatter the vegetation?
disable windows page file for giggles, will work if OS issue, but wont if 3dsmax issue
Step 1: render with gray mtl override, see if it helps
I will check the OS cache story for sure but I agree, excellent idea to grey material render and rule out any textures first! I used Corona Scatter as well as Forest Pack and HD Plants / xFrog Plants.
