OTOY Forums

Hi all

is there a chart for how much GPU RAM is used, for both textures and geometry?

We're looking in to a system which will handle around 20 million poly+ and render out at 10K.

Cheers

well, octane use no VRAM for texture with the "out of core" option, and use 2.2 GB VRAM for 20 millions triangles.
The rule would be with 1 GB VRAM you can render 9 millions triangles.

Also the image buffer doesn't take much VRAM, you can reduce it to allmost nothing with "parallele sample" = 1, at the cost of a little speed.

Hi Calus

Thanks for the info.

When you say 'image buffer', is this the amount of RAM used for saving out the 10K image?
As for the parallele sample, do I set this parameter in the render settings?

Thanks again.

I think there is not a constant to calculate RAM from triangles counts. It can change if you have motion blur or extra uvs. also how much mesh nodes.
And renderbuffers take some VRAM(or RAM when VRAM full on V3). formula is W*H*16 bytes per buffer.

aoktar wrote:I think there is not a constant to calculate RAM from triangles counts. It can change if you have motion blur or extra uvs. also how much mesh nodes.

Right, I forgot about that.

prodviz wrote: When you say 'image buffer', is this the amount of RAM used for saving out the 10K image?

yes

and about "parallele samples" its an option in V3 rendsetting yes, you were talking about V3 right ?
if you were talking about V2, it's limited to 19 millions triangles in any case.
(Aoktar made a nice board about that )

Cool.

I'm on V2 at the mo (and V2 Maya plugin), so am looking at the 19 mill cap.

Is 'W*H*16 bytes per buffer' width and height?

Thanks again.

prodviz wrote:Cool.

I'm on V2 at the mo (and V2 Maya plugin), so am looking at the 19 mill cap.

Is 'W*H*16 bytes per buffer' width and height?

Thanks again.

yes. Also passes are same seperately. But z-depth and someone is grayscale. So one pixel is not 16-bytes on these maybe 4-bytes. Btw V3 can use system RAM for buffers when VRAM full.