Do you have the all access subscription ? If so then it sounds a bit strange .
The previous 2018 build worked fine for me.

??? I bought a one year all access subscription and I have checked my licence with the plugin but it is still only rendering with 2 gpus .
Am I right in assuming that I only have access to octane 4 builds and 2018 builds will only use 2 gpus ? as the previous 2018 builds worked fine ....but now Im ...

Same here.. comes up with warnings and it will only render on 2 gpu's.

Any chance of getting this resolved asap please as Ive got a render to do and Ive already switched over to 17.5.

I have repeatable crash caused by applying open subdiv in the spare properties when Cd attribute is being used on the mesh and accessed in the material graph.
Houdini gets to a certain point loading and then disappears.

Are you talking about the Octane native opensubd feature? I know that there ...

I have repeatable crash caused by applying open subdiv in the spare properties when Cd attribute is being used on the mesh and accessed in the material graph.
Houdini gets to a certain point loading and then disappears.