No Optix option available for GTX cards? (denoise is working and in terminal it says Optix available)

[juangea]

I can't find a way to enable Optix with my GTX1080, I mean the raytracing features, not the denoiser, it used to be an option in settings, but there is no option anymore, any ideas?

Thanks!

[Dade916]

Optix is a lot slower than our code on my GTX980 (and some other people GTX): the Optix/RTX support is disabled by default in LuxCore for no RTX cards (and the option may have been hidden on BlendLuxCore for that kind of GPUs, not sure).

[juangea]

Hey @Dade916 based on my testing with Cycles, Optix is slower in some GTX cards but faster in others, for example the 1080 and the 1080Ti are faster, while the 1070 is slower, also the 980m (I have a laptop with two of them) are faster.

Could be a good idea to be able to enable it, maybe under a hidden option in devices, or under a warning or advanced section, something like that, but with the 1080 it should be faster, I think it's related to memory bandwidth available in the different GPU's, at least I think I remember that this was the only explanation I could find.

Is there a way I can force to enable Optix and recompile kernels?

[MarkBTomlinson]

I have just been looking and was confused by the Optix not available on my GTX1080 as it is available and works well in Cycles. As others mention an option to enable this and change the message displayed warning of it being potentially slower may be helpful.