I just tried it locally and this is what I get:
10K hairs: 6 sec
40K hairs: 7 sec
Which versions of Max, Ornatrix, and Windows are you using? Do you use any specific MR shaders in your scene? Does this happen in a blank new scene? If not, can you send your scene to us for testing?
Thank you
Marsel Khadiyev (Software Developer, EPHERE Inc.)