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Hi there,

I need little help

I bought octane today, and one thing I noticed that the total vram octane is showing to me is 8 gb only.

So will octane handle my big scenes without showing out of memory error?

I have four gpu :

nvidia 3090 with 24 gb ram

nvidia 3070 with 10 gb

nvidia 3060 ti with 8 gb

and nvidia 3060 with 12 gb

Please let me know..thank you

As of this writing, in most cases Octane does not pool (or combine) VRAM from multiple cards. It uses the VRAM in the card with the LEAST amount, and then any additional textures or geometry is loaded into system RAM (this is called Out-of-Core memory, or OoC). For example, if you were to put a 24GB card and a 4GB card in, you’d only be able to utilize 4GB of VRAM before it overflows into system RAM (unless you disabled the 4GB card in the Octane settings). Also, scenes loaded into OoC memory currently can’t use RTX acceleration.

The latter position is especially disappointing, since it shows that the much-advertised RTX function is very seriously limited if you have difficult scenes, but there is no NVLink or there is no video card with 24-48 gigabytes of memory.
By and large, over the past few years, the entire development of Octane was at the expense of Nvidia. But now Nvidia will not help much if the Octane developers continue to sit idly by.

elsksa wrote:This page should greatly cover many of commonly asked Octane-hardware questions: https://help.otoy.com/hc/en-us/articles ... taneRender

"If you have one RTX 3090 with 24GB of VRAM, you will already want three to four times the amount of system RAM in order to fully fill it (this varies depending on the scene and other RAM usage in your system). This means you’re looking at a minimum of 72GB of system RAM to keep everything happy. If you are running two 3090s that are connected via NVLink, you will actually want a minimum of 144GB of RAM"

144GB RAM to use two 3090 ? Can anyone confirm this ?

SSmolak wrote:

elsksa wrote:This page should greatly cover many of commonly asked Octane-hardware questions: https://help.otoy.com/hc/en-us/articles ... taneRender

"If you have one RTX 3090 with 24GB of VRAM, you will already want three to four times the amount of system RAM in order to fully fill it (this varies depending on the scene and other RAM usage in your system). This means you’re looking at a minimum of 72GB of system RAM to keep everything happy. If you are running two 3090s that are connected via NVLink, you will actually want a minimum of 144GB of RAM"

144GB RAM to use two 3090 ? Can anyone confirm this ?

I can confirm this at least with my RTX Titans (24GB each) in SLI / with NVLink.
I have 128 GB system Ram and that almost runs out when both cards are tested using the maximum Vram on my cards. Keep in mind I never get 48GB "Shared" or "Pooled" Vram. The most I think I got was 40 GB utilized because of windows reserved memory and other stuff.
So...40GB Vram x 3 = 120GB System Ram needed...sounds about right. It's a good guideline to follow for now.

Thank you for confirmation. Also how much unavailable Vram do you have while opening empty scene showed in Octane Device Preferences ? I have enabled Win10 GPU Scheduling but Octane shows that 1.5-1.9 GB Vram is unavailable on my two RTX 3090. Is it normal ?

[quote="SSmolak"]Thank you for confirmation. Also how much unavailable Vram do you have while opening empty scene showed in Octane Device Preferences ? I have enabled Win10 GPU Scheduling but Octane shows that 1.5-1.9 GB Vram is unavailable on my two RTX 3090. Is it normal ?[/quot

I have 1.5 GB Vram unavailable on my two Titans also on an empty scene. I have the same value with Win10 GPU Scheduling on and off. Your data seems on par with mine...I guess it's normal. (?)
Last year Windows would reserve much more Vram..much better now on empty scenes as well as rendering heavy scenes.

dynaraton wrote:I have the same value with Win10 GPU Scheduling on and off. Your data seems on par with mine...I guess it's normal. (?)
Last year Windows would reserve much more Vram..much better now on empty scenes as well as rendering heavy scenes.
Do you have NVLink installed on your 3090's?

As I remember when they introducing GPU scheduling I had more free Vram available. At the moment switching this on/off give the same amount. Yes I have them NVlinked.