I noticed these artifacts with some fabric scans on Vray Next GPU
RT CPU will render them fine, but on GPU I get this result,
This happens with like 80% of the fabric scans that I tested, But few other fabric scans will render just fine.
System specs,
Windows 10 1809
Maya 2018.4
Vray Next for Maya hotfix 1
GTX 1080Ti x 3
Nvidia drivers 416.94
I also tried on my Imac Pro and I can reproduce the same behavior,
OSX 10.13.6 High Sierra
Maya 2018.4
Vray Next for Maya hotfix 1
GTX 1080Ti
Web drivers,
Thanks for the report Muhammed!
Just to clarify - under “black aretifacts” you understand these two vertical slits didn’t you? We will download and investigate the scene, but perhaps the GPU team will investigate the problem, so until they start you can help us answering some quastios:
- Is the problem related to the “edges displacement” option, i.e. is it dissapearing if the option is disabled or enabled?
- Is the problem related to the transparency, i.e. what happens if you disable/enable it?
- is the fabric geometry confined or is just a deformed plane ?
Yeah, the vertical slits are what I meant. Sorry for bad English.
I get the same behavior turning it on/off
And by the way, these vertical slits don't show in light cache prepass.. it only shows after GPU buckets are finished or in IPR mode which doesn't use Light Cache 
\- is the fabric geometry confined or is just a deformed plane ?
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It is not a plane.. The geometry has thickness and it is waterproof, but I just realized It has polysmoothSurface with subdivision set to 1
I did collapse the mesh, but still I get the exact same results
But if I set the polysmooth surface to 0 then collapse my mesh I get different kind of artifacts, 
Hiding the geometry behind it, it seems the vertical slits are transparent, not black
Also here is another fabric scan that renders completely fine(20% of the fabrics will render fine without the slits, all leather scans will render fine too)
