luketulley Posted May 1, 2016 Share Posted May 1, 2016 I've just started testing out RT GPU rendering for the first time and I seem to be getting excessive render times (8 hours) to produce near noiseless images (max. noise 0.02) for relatively simple interior scenes. Obviously with optimisation vray adv can outperform these render times ten fold. I believe I have set everything up right in RT: CUDA, in process, coherent tracing, max render time 0, ray bundle size (512), Rays per pixel (128), Trace Depth 5, resize textures, disabled probablistic. I'm also using light cache (+glossy rays). I can see that material / light subdivs etc aren't applicable so I'm wondering what could be the cause of these excessive render times - or is this expected?? Workstation config: Titan X 5960X 64gb ballistix sport 3dsmax 2016 vray 3.3 FYI. We had anticipated using rt as part of our sign off process & purchasing another titan x but we're unsure if it is a wise choice now... Any comments / advice etc will be appreciated! Link to comment Share on other sites More sharing options...
Scott Schroeder Posted May 1, 2016 Share Posted May 1, 2016 What is your scene consist of? What size are you rendering to? You could be hitting the RAM limit on your card. Plus you are having to resize all of your textures to a power of 2 and preferably square, with the resize texture option on, that will fill up your memory as well. RT does dump back to the system RAM once your GPU RAM is maxed, but that increases your render time. If you are not properly prepping a scene for RT, then it's not some ultra speedy magic bullet solution. While highly unoptimized scenes don't see too much of a hit in normal rendering, it gets magnified on the GPU. Link to comment Share on other sites More sharing options...
luketulley Posted May 2, 2016 Author Share Posted May 2, 2016 Hi Scott.. Cheers for the response, I'm honestly loosing my mind here as these render times are insulting to say the least! I'm rendering out to 4000 x 2250px - not the smallest I know but I've also tried 1920x1080 and that's still ridiculous. I've tested a new scene that consists of 4 walls, ceiling, floor, 3 windows & a dome light (Guthrie HDRI - no other maps) - & I'm still getting the same kind of render times.. I'm utilising ggx shaders for glass plastic & paint but I've also tested without. I'm using a max physical cam with pretty standard settings - no dof or mb. I've tested cycling up and down with the bundle size & rays per pixel to double check that I'm not overdoing it in terms of memory... In terms of optimisation; I guess that you are referring to modelling wise (proxies etc) as all material / light subdivs etc are unavailable , if so then I'm pretty sure our models are more than adequate - this also reflects in the vray messages showing 10gb+ gpu ram still available at render time. I'm pretty sure that something is amiss as my last test scene couldn't get much simpler. Any thoughts on how to proceed? Link to comment Share on other sites More sharing options...
erkutacar Posted May 2, 2016 Share Posted May 2, 2016 r u sure ur card is selected in the OpenCL options? Link to comment Share on other sites More sharing options...
luketulley Posted May 2, 2016 Author Share Posted May 2, 2016 Yeah. I can also see in GPU-Z that the card is getting 99% GPU load when rendering - memory used never gets above 4666mb - GPU Core Clock 1303 - GPU Mem Clock 1652 - mem controler load averages at about 10% Link to comment Share on other sites More sharing options...
luketulley Posted May 2, 2016 Author Share Posted May 2, 2016 PS. I have the engine type set to CUDA. OpenCL simply doesn't render at all... Link to comment Share on other sites More sharing options...
joelmcwilliam Posted May 2, 2016 Share Posted May 2, 2016 Dude, that is some powerfull hardware you've got there. Honestly, i've never used rt, but I think your problem has to do something with the software. Maybe you can find a solution here: http://www.renderspaz.com/tutorials/vray/ Sorry that i can't help u more. Link to comment Share on other sites More sharing options...
luketulley Posted May 2, 2016 Author Share Posted May 2, 2016 Dude, that is some powerfull hardware you've got there. Honestly, i've never used rt, but I think your problem has to do something with the software. Maybe you can find a solution here: http://www.renderspaz.com/tutorials/vray/ Sorry that i can't help u more. Cheers Joel. Link to comment Share on other sites More sharing options...
luketulley Posted May 3, 2016 Author Share Posted May 3, 2016 A quick update - new test scene again: Reset Max. One standard 1000mm box. One ground plane. Standard material throughout. Single HDRI (Guthrie) in Dome 4000 x 2250px RT al the same as above... 3 hours + render times - I got bored of the same 4 walls so I stopped it at that point Has anyone had the same kind of issues or does anybody have any inclination as to why this is rendering so slowly? Driver issues etc? Surely for 7 polys, a standard material & a hdri this cannot be correct? Link to comment Share on other sites More sharing options...
joelmcwilliam Posted May 3, 2016 Share Posted May 3, 2016 What driver are you using for the gpu? The latest and greatest? The most sensible thing i can say is try using some of the older drivers and see how that works out. Like you said, there could be an driver issue. You can also send an email to the software manufacturer and see what their respond is. Do you have another gpu lying around? Link to comment Share on other sites More sharing options...
luketulley Posted May 4, 2016 Author Share Posted May 4, 2016 Of course the latest and greatest (stupidly installed Geforce Experience which has kept me up to date), I tried rolling back to an earlier version which didn't work out to well as it gave me a black screen and an endless reboot loop. I'm going to have to bench it for a week or two now anyway as we're stacked with work, but I have just snapped up a secondary Titan X to test to see if there is any joy with another card - failing that onto Chaos Group. I'll keep the thread updated with any progress. Cheers Link to comment Share on other sites More sharing options...
Rich O Posted May 5, 2016 Share Posted May 5, 2016 I'd be interested to know the reasons for this; post in the problems section on the Chaos forums? Link to comment Share on other sites More sharing options...
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