But you should try to get a card (if you don’t already have one) that will have at least 2GB of VRAM and those are plentiful now at much lower prices. You can do it with 1.2 or 1.5GB. The goal of many Octane users is to save for a Titan card (6GB).
This pretty much sums it up.
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My personal user experience is based on a
Asus GTX660 Ti DCII OC, 2048MB GDDR5, 6008/967 MHz
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It is very important to stress that high resolution 4000x4000 textures really take up much space. Especially if PA use high resolution ones for every single material zone no matter how small it ends up being in the final render.
Examples: Stonemason and Dream Light transform into Octane very well without even reaching the limits on my 2GB card.
Most Jack Tomalin scenes will flood the VRAM very quickly.
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To work with this the octane plugin has the option to load only the geometry. After the geometry is loaded you then have the option from directly the octane render viewport to select any material surface that is still untextured white and load the DS presets for that specific surface.
This way you can pretty much keep the texture count low by only loading those textures that will be visible.
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Another big help is the Octane live material database. Instead of using textures that stress the VRAM you can use Octane Shaders.
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Which card to buy now?
If I would buy a card right now with a low budget I would try to get a card with at least 3GB of VRAM.
If you are lucky you can find a 3GB version of the GTX660 Ti .
If a Titan is too expensive maybe the next few months will see new options.
Some consumer level Titan cards are rumored.
If you are a patient person who does not expect a complete scene to fit into the VRAM and are up for a bit of memory managing 2GB may be enough if you do not want to render images much larger than 1920x1080.
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This was posted on the octane user forum. I hope it is ok if I post this here as well:
The question was:
Can someone point me in the direction of a forum thread / webpage where VRAM and how its size is calculated is explained?
The answer was:
don’t know one; it is easy to tell for textures:
- a grayscale image needs x pixels * y pixels in bytes
- a color image needs x pixels * y pixels * 4 in bytes
note: the plugin/octane only uses a texture map once per type; if you use the same image in 10 slots while maintaining the same type (floatimage vs. image) it’ll need vram only once. if you mix types, octane will need vram once per type. the way how octane finds out about multiple uses of the same texture map by the way is the path on disk; using the very same image map from different locations will also require more vram.
in addition the render film (aka output image) - as long as stored in vram…
- needs x pixels * y pixels * 20 in bytes
(this is because the render film holds not only 4 bytes of color data, but additional data need to calculate tonemapping, post processing, ...)
you can neglect node parameter data; this ranges in kilobytes.
the geometry itself would need to be counted; and the plain number of triangles don’t exactly result in the vram size needed, since octane does something called voxelizing, where at least i don’t know a formula to calculate the real need. hopefully we see some additional stats from the octane plugin version anytime soon, so it would be possible to at least show those numbers when voxelizing is done.
if you like to do some research yourself, you may use the standalone - there you will get all those numbers, including geometry data ram usage…
I can only add that the VRAM size of the actual render may push past the limits if you want to render out images at larger sizes like 4000x6000. That was one aspect I did originally not think about. If you set up scenes for testing and have the preview at 720x480 in most cases it was no issue to raise the render size to 1920x1080. But sometimes when I wanted to push past that to 6000x4000 I was out of VRAM again and had to make some more adjustments.
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The best thing to do atm seems to get the Octane Render stand alone demo and see how that works for you.
A demo for the DS plugin for Octane may be released when most bugs are dealt with.
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