Graphic Card Memory for GPU Rendering Vray

[Guest yanisamasri]

Hi , I would like to know what the RAM on the graphics cards do in GPU render with Vray .

I want to buy the new GTX Titan X for Vray RT ( 12gb )

Or the GTX Titan Z , but is really expensive

 

Thanks

[Nikolaos M]

Lets wait to see TitanX's price first. For ~1000$ it would be an interesting case, mostly because of the 12gb of VRAM and the Maxwell architecture. For over 1300$, hmm... I don't know.

I would personally wait for the 8gb versions of gtx 970 and 980. Titan X is expected to have ~ 3000 cuda cores. Imagine that right now with aprox 1000$ someone could buy 3xgtx970 with aproc 5100 cuda cores, i.e. 70% more cores with the same budget, but with the restraint of 4gb of VRAM. And, as far as I know, gpu rendering needs the biggest amount of cores that your money can buy. The more the better. As for the VRAM you need, only you can answer this. Have you ever mesured the gpu utilization with your current rig? For example, my gtx 780 with 3gb VRAM is more than enough for the use I make in 3ds max. My models are very simple for now. So, in your place, if I was planning to get involved with gpu rendering in iray etc, I would probably buy 2 or 3 gtx 970's or as many of them as I could. But if you work on complex scenes and extremely high poly models, then maybe you should wait for editions with more VRAM.

Edited March 12, 2015 by nikolaosm

[Guest yanisamasri]

Ok thanks !

So the 12gb of Vram in the GTX titan X isnt so important for the GPU rendering on Vray ?

The Cuda Cores is what the render need to go fast no ?

[Nikolaos M]

I didn't say that. I said that the amount of VRAM you really need could only be estimated by you and no one else. I think that 12gb is a bit too much for the average designer right now, but I would probably wait for the 8gb versions of 970 and 980. I haven't really made a lot of tests with iray personally, so I don't exactly know if there is a specific change of the VRAM use between viewport and rendering procedure.

[Guest yanisamasri]

Ok ��

[Guest yanisamasri]

Ok But I dont know the amount of VRAM that I need because i dont understand what the Graphic Card Vram does in the render !

Sorry , im not an expert in computer ... Hahaha

[RyderSK]

I have bit polar opinion, as often I max out the 32GB limit of conventional CPU rendering, even 12GB isn't miracle. But GPU renders are more effiecient in memory storage, so in practicality (this isn't conversion, just laic approx) 12GB on Vram use in GPU renderer can equal 20gb+ in system memory use of CPU renderer (because they often store less info, don't support as many features, options..)

Then there is memory cycling/out of core rendering goes around this limitation at performance cost. Redshift renderer is capable of it.

 

Still, Titan-X is imho the only viable card for true archviz GPU rendering. It looks right now like single gpu card unlike Titan-Z fail.

Second option would be upcoming GTX 980 with 8GB, but anything else....rather not. I would rather pay more for less power, but actually be able to render my scenes without wasting time to optimize heavily (by hiding everything left and right for each camera).

 

But really, if you're interested in going GPU-rendering, you should at least check their F.A.Q on website (Redshift, Octane, Arion, iRay, Thea, VrayRT-GPU....).

 

How much GPU memory is needed for 3ds Max iray rendering?

The entire scene must fit into GPU graphics memory in order for iray to take advantage of GPU acceleration. If the scene does not fit unto into a GPU’s memory, that GPU is ignored and all processing takes place on the CPU and in RAM and run much more slowly. If the scene exceeds RAM, then iray will use virtual memory and run more slowly yet. For estimating memory usage, budget about 1 GB per 8 million triangles, to which you must also add 3 bytes/pixel for any referenced bitmaps.

{iRay f.a.q link}

Edited March 13, 2015 by RyderSK