more number of graphics cards, or less but more powerful?

[urtcor]

Hi!
I'm a 3D artist and I'm thinking about buying a PC for use the famous Octane (I have a Mac Pro late 2013) but I'm a little confused.
I want to focus on VERY FAST render, si I'm thinking on something like 4x GTX 1070... but I don't know if it's a good option. It's better 4x 1070 or 2x Titan? Or 2x latest 1080 ti? It's a good choice 4x 1070 although it has less CUDA cores? or it's better to have just one very powerfull?

Thanks!!

[glimpse]

it very much depends on Your needs for speed & future plans for upgrading the system.

1070s now seems to give a good value if You do not need more than 8GB of vram & focus more on speed.
if amount of vram is important & You plan to have a need for more than 8GB then look at 1080Ti with 11GB.

last but not least think about upgradeability & portability of Your box. For instance if You plan to expand sometimes it's worth to invest into more powerful cards that would allow You to keep them & add more rather than replacing existing ;) Another thing, if You have to move Your box, again think about less but powerful cards to save some space & minimize dimensions of Your machine. Also, what is Your upgrade cycle? if You plan to use Your computer for three years, getting higher end cards might be wise idea.

it's hard to recommend without knowing what You're up to, but overall try to look at reference/founders 1070s or 1080tis.

let us know if You would still have some questions.

[urtcor]

it very much depends on Your needs for speed & future plans for upgrading the system.

1070s now seems to give a good value if You do not need more than 8GB of vram & focus more on speed.
if amount of vram is important & You plan to have a need for more than 8GB then look at 1080Ti with 11GB.

last but not least think about upgradeability & portability of Your box. For instance if You plan to expand sometimes it's worth to invest into more powerful cards that would allow You to keep them & add more rather than replacing existing Another thing, if You have to move Your box, again think about less but powerful cards to save some space & minimize dimensions of Your machine. Also, what is Your upgrade cycle? if You plan to use Your computer for three years, getting higher end cards might be wise idea.

it's hard to recommend without knowing what You're up to, but overall try to look at reference/founders 1070s or 1080tis.

let us know if You would still have some questions.

Hi!
Thank you very much glimpse for your reply! I think I will use the computer about 4 or 5 years (I'm not used to PCs, but I hope it will work for a long time). For me the amount of vram is quite important because sometimes I work in projects with a big amount of polygons...

Regarding of the amount of GB and CUDA cores, I have a big question about how the GPU render works: I understant that when you render with Octane, all the graphic card works like one? So with x4 1070 I will have 32 GB vram, isn't it? and 1920x4 CUDA cores? So technically (and cheaper) is it better to have 4 1070?

Thanks!

[mr_seq]

Regarding of the amount of GB and CUDA cores, I have a big question about how the GPU render works: I understant that when you render with Octane, all the graphic card works like one? So with x4 1070 I will have 32 GB vram, isn't it? and 1920x4 CUDA cores? So technically (and cheaper) is it better to have 4 1070?

About the total amount of vram: no, it's not combined, Linus explains it pretty clear here: https://www.youtube.com/watch?v=Utv144XeHag
Not sure about the CUDA cores though..

[urtcor]

Regarding of the amount of GB and CUDA cores, I have a big question about how the GPU render works: I understant that when you render with Octane, all the graphic card works like one? So with x4 1070 I will have 32 GB vram, isn't it? and 1920x4 CUDA cores? So technically (and cheaper) is it better to have 4 1070?

About the total amount of vram: no, it's not combined, Linus explains it pretty clear here: https://www.youtube.com/watch?v=Utv144XeHag
Not sure about the CUDA cores though..

Thank you very much mr_seq, very interesting the video

[jsuarez388]

From what I know (I've been using Octane for 2+ years) VRAM doesn't add up. And this is something important to keep in mind. If you get let's say 2x 1070s and then plan to add a 1080, you are stock with the 8GB of VRAM of the 1070.

As for cuda cores, Octane feeds on cuda cores, so these do scale/add up.

For example:
4x 1070s = 7680 Cuda cores > This will cost you roughly $1,516
2x 1080tis = 7160 Cuda Cores > This will cost you roughly $1,400

So about $116 gets you 520 Cuda cores but limits you to 8gb of VRAM vs 11GB. Way more speed vs less VRAM.

What did you end up doing? I'm curious...

[JasmineJasmine]

From what I know (I've been using Octane for 2+ years) VRAM doesn't add up. And this is something important to keep in mind. If you get let's say 2x 1070s and then plan to add a 1080, you are stock with the 8GB of VRAM of the 1070.

As for cuda cores, Octane feeds on cuda cores, so these do scale/add up.

For example:
4x 1070s = 7680 Cuda cores > This will cost you roughly $1,516
2x 1080tis = 7160 Cuda Cores > This will cost you roughly $1,400

So about $116 gets you 520 Cuda cores but limits you to 8gb of VRAM vs 11GB. Way more speed vs less VRAM.

What did you end up doing? I'm curious...

interesting view

[showme]

True

Octane will pick the lowest card and limit the VRAM to that card so be careful cramming your system with cards of different specs.