Has anybody used V-Ray Next for an interior yet? I haven’t been able to get one to render without extreme render times. An interior that was rendering with 3.6 was taking a couple hours and now, 7+ hours and still noisy. I started another interior today, which is really rather simple, and I am experiencing the same insane render times. I am zipping them up now and I will post, but I just wanted to see if it is just an issue here or if others are experiencing higher render times, too.
I brought it over to another fine Chaos Group software, Corona. After the conversion and the initial render my walls had something strange going on, so I swapped it out with a Corona wall material, which corrected that issue. I let Corona run for about 1 1/2 hours and it is pretty clean; another 1/2 an hour and it would be good. I am not sure what Corona is doing that VRay Next is chocking on, but it is doing the job. I do like the post tools in Corona. The LUT opacity is a must, so hopefully, V-Ray adopts that. This isn’t meant to be a Corona vs. V-Ray, but I would be interested in what I am doing wrong for my V-Ray NEXT times being 7+ hours and still not very clean.
Something really strange is going on with my walls. Corona was rendering things beautifully, but like usual, I stopped it to tweak something. After I restarted the render I saw this strange banding on my wall again. I tweaked something that has nothing to do with the walls and after checking the wall material, some transparent banding got introduced somehow. The material is from Siger Shaders and I never had a problem with their interior paint material before.
Sounds strange, I happened to be doing an interior renders project during 3.6 and then with NEXT. Experienced nothing like you are, render times were an improvement.
I downloaded the model and had a look. Probably rather pointless seeing that I dont have Next yet 
or that non of the textures were included which would have made things a bit easier to trouble shoot.
Anyway I ended up resetting the render settings to default then tweaking a few settings, nothing crazy.
Redid most of the lighting by swatting out the IES for Vray lights, deleting the Vray sun (by the way the daylight system was still using a skylight), replaces it with two plane lights in the window.
Did a simple white material over ride for everything except the ceiling lights
This took 58 minutes on a single machine
@glorybound Very quick test
Scene on Vray Next. You didn’t add any assets for lights so i just used Nice IES 30 and changed the camera settings to a more reasonable interior setting.
F5.6 / Shutter 1/100 and ISO 200
4k in 10m on a 72 core machine. Noise threshold .01. You could just add the denoiser ontop with custom 0.65 to clean any noticeable noise up even further
Although you had DOF turned on i turned it off - tested again with it on and still 10 mins
Can send the scene via your email you want it
Typical, blaming vray for the PEBCAK
Must admit, I had to look that one up…
Personally, whenever I have a hardware/software problem, I typically always first think it’s me that’s the issue… and I’m usually right 
Yes, I would love to see the scene. whitebirchstudios@gmail.com I tried every combination, so I could be having PC issues. Things haven’t been running right since Microsofts Spring update.
If you read my original post, I say that it might very well be me. Even my Photoshop is running slow.
Well i can send it over. But FYI when i rendered with your camera F1.4 at 4k Override on it was slow as. Thats why i changed the camera settings
We used to call that an id10t error.
I did try turning off DOF, but I don’t remember that helping. I am downloading your file now, thank you.
I spend all week trying to get reasonable render time, trying everything. I downloaded the scene you sent, turned on the materials and it is rendering fine. I am stumped! It couldn’t be just the DOF and IES, since I tried turning both off and it didn’t help. I wonder if opening up on a new machine with a reset V-Ray fixed something eternal (I tried resetting V-Ray). At some point, I did turn on auto exposure and color balance and my scene rendered almost black. Anyway, thank you for taking the time to help. I owe you one!
Wouldn’t you say an hour with no materials is rather high?
Tbh @glorybound i didnt reset anything. I could be completely wrong but try changing back to your old camera settings and adjust the lights back and render. I had a feeling that it was the camera settings. Its happened to me before where i got strange render times with certain camera settings.
I had some issues this week, vray3.6, where I was using very low EV settings (1 or 2…) to have enough light in the image. Was using a HDRI domelight (pg skies), adding portals seemed to do f-all. Vray settings were standard BF/LC. Admittedly it was a deep building with relatively small windows so it was tough to balance the areas near the windows vs the deeper areas. That really caused a lot of noise issues. Ended up faking some soft general lighting with vray sfere’s. Still wasn’t great though. It was that bad in the dark parts with dark materials that the denoiser didn’t even seem to do anything. Ended up rendering the problem shots with extra light and in post brought back dark areas from the original lighting from the tests shots.
Bobby did you setup your render slave box?
No, not yet. I put an ad on craigslist, but everyone flaked out on me. I spent some time and I thought I got it, but nope. I switched around some cables, turned off my Pixelbook’s WIFI and plugged in the data cable and it worked, but when I brought my Pixelbook to my office and plugged it in, it didn’t work. I’ll spend some more time this weekend.
Sounds like a DHCP problem.