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i cant have fun with octane
because of my vcard quadro fx1700 is not supported
maybe i'll just wait for bunkspeed shot,

Buy a cheap gtx260. It costs close to nothing. works decent.

Try Craigslist, I see NVida cards for sale there all the time.... dirt cheap!

jdomingo wrote:i cant have fun with octane

I hear ya bud. I am in the waiting area too.

My current card: ATI Radeon X1300. 256MB of non-CUDA enabled coolness.

The GTS 240 is on its way, but won't get here till Thursday. So It'll be you and me for a while in the pen.

The Quadro FX1700 is cuda enabled so you can use it for Octane but it has 32 cores so it will be quite slow and so not really suitable.
You could probably play with the demo a little just to see what its about though.
You would need to use the Octane8000.exe and Quadro driver 191.78.
The 1700 would be useful for display if you get a gaming card to dedicate to Octane use and put it in another pci-e slot.
I did this with a GTS250/1GB and a FX570 (the little brother of the 1700) using a modded Quadro driver and it works well.
Beware though if you use 32 bit that the vram eats into your available system ram so you will need to have 4gb and run the 3gb switch to get the most out of the vram space for Octane.
The FX1700 has 512mb + GTX260 896mb is much the same total as FX570 256mb + GTS 250 1gb. You'll end up with about 2700mb available ram in that case which is about as much space as the 3gb switch will practically yeild anyway even if the O/S didnt take up some of it.
Beware too that an FX570,1700 or 3700 must be in the primary slot - they dont work as secondary cards -its a known issue.
You will need the ram and a heap of pagefile to load large .obj into Octane.
I found a limit for loading at about 2.5million polys and it will use 2gb of both ram and page for that. The polys by themselves fill about 400mb in Octane/vram.
A 1.5, 1.8 or 2gb card for 32 bit is just going to take up valuable system ram and you wont be able to utilise the extra space directly.
HTH

pixelrush wrote:The FX1700 has 512mb + GTX260 896mb is much the same total as FX570 256mb + GTS 250 1gb. You'll end up with about 2700mb available ram in that case which is about as much space as the 3gb switch will practically yeild anyway even if the O/S didnt take up some of it.
[SNIP]
You will need the ram and a heap of pagefile to load large .obj into Octane.
I found a limit for loading at about 2.5million polys and it will use 2gb of both ram and page for that. The polys by themselves fill about 400mb in Octane/vram.
A 1.5, 1.8 or 2gb card for 32 bit is just going to take up valuable system ram and you wont be able to utilise the extra space directly.
HTH

I guess I need some clarification. I thought Octane ran entirely on the GPU utilizing the VRAM on the card only. Is that not the case?

How does Octane use system resources (on say, for example, a Win32 system)?

Well Octane does run on Cuda in vram but you need to prepare and load the data in from disk via the cpu and manage the data in/out and across gpus.
If you watch the system ram use in Win Task Manager as Octane loads a scene use is resembles exponential curve peaking after the voxelising phase and then it drops off a bit to stable running.
In the max example I mentioned above it stabilised at about 1.4gb pagefile IIRC and my dual core ran at 50% utilisation each core during the render. Sorry I can remember how much sys ram was in use.
The gpu is definitely doing the heavy work but the cpu is moderately busy managing it all.
To answer your question more directly the cpu doesnt sit idle with 300mb ram use as if you had no application open while the gpu is full on working on the render calcs.
HTH

Edit: Just to clarify, Windows uses some of its ram space to buffer the vram.
If you add in a second gpu with 1gb vram thats going to mean 1gb less sys ram available for actual program use. In 32 bit there is a trade off between adding vram for Octane space and having enough sys ram available to prepare the data and load it.
32bit is limited to 4gb address space max or 2gb per application (actually about 1.7gb) unless you enable the 3gb switch in Win Professional which yeilds about 2.7 gb.
64 bit is the way to go. I understand Win7 is a bit different re memory management too which would be helpful.
I would guess you will need something like 12gb of ram to load a 4gb Quadro or 6gb Tesla card and 8gb to load a 3gb card.
I am not sure how it would all work in the case of multiple gpu used for Octane.

So as to not further this highjack (and give this topic its own thread which I think it deserves):

http://www.refractivesoftware.com/forum ... f=12&t=453

thwak wrote:So as to not further this highjack (and give this topic its own thread which I think it deserves):

no problem hi jacking this thread, i just dont understand to much technicality what running inside my pc.

to pc guru out there, i wanted to upgrade my system so that i can play octane. what should i upgrade? my system below:

-dell precision workstation t7400
-window 64bit
-4 gb ram
-intel xeon E5420 @ 2.5ghz
-nvidia quadro fx1700

if its the graphic card only, what is the best of the best out there?

thanks for your reply.

jdomingo wrote:no problem hi jacking this thread

Well, the other thread that I started has received zero attention, so clearly it wasn't as important a subject as I thought.

jdomingo wrote:if its the graphic card only, what is the best of the best out there?

The card that Radiance is currently recommending is the GTX 260 as it currently has the best bang for the buck performance ratio according to him. If you want to see all the cards that are available look here:

http://www.nvidia.com/object/geforce_family.html

Get something in the 200-series and you should be fine.