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InfoBrain wrote:So when multi GPU support is available 2 X 470 would be better than a single 480, nearly twice the cores and memory from both cards would be available for rendering 3GB+/- correct? Or will we still only be able to use memory from 1 card and just the additional cores from the second GPU

I was going to order a single 480 today, my PS is only 750 and will only support one and I was going to use one of my 9800gt's for OS, but then I found Newegg has a special combo "today only" 2 x EVGA 470 + Corsair 950 PS for $709.98 US. http://www.newegg.com/Product/ComboDeal ... mbo.390415

So for less than $200 more I can have almost 2 times 480 with a 950 PS, but can anyone confirm that a 950 PS is going to be enough power to support 2 x 470???

no, the memory will stay the same as one card.
if you use more than one GPU at the same time with 2.2, you can have available for use, the memory size of the smallest of the GPUs you put in it.

if you render with 2x GTX470 you will have less memory than with one GTX480

Radiance

Hi, With two GTX 470 you will have 2 x 448 cores = 896 cores, versus 480 cores with a GTX 480,

BUT : these cores will work at lower frequency : 1215 MHz versus 1401 MHz, and The most important for working with Octane is that you will have only 1280MB of VRAM versus 1535MB with GTX 480.

Memory is not cumulative,and the whole project is loaded in the two cards at the same time, so even with two cards, the availablememory amount is the amount of the card that has the less memory. If you have two identical cards, for example two GTX 470, you will have only 1280 MB to host your scenes.

For the corsair PSU, if it is a TX950W, it looks like very powerful one. It is a 12 volt monorail Power supply unit providing up to 78 A that you can distribute to everything you want, so it should be suitable for two GTX 470 or even GTX 480 with a safety margin.

http://www.corsair.com/products/tx950/default.aspx

IMPORTANT NOTE WHEN CHOOSING A NEW PSU : Verify the ATX version compatibility with your Motherboard !

Edit : I see that radiance has answered while I was typing my post !

ROUBAL wrote:Hi, With two GTX 470 you will have 2 x 448 cores = 896 cores, versus 480 cores with a GTX 480,

BUT : these cores will work at lower frequency : 1215 MHz versus 1401 MHz, and The most important for working with Octane is that you will have only 1280MB of VRAM versus 1535MB with GTX 480.

but if memory isn't an issue wouldn't 896 cores running at 1215 MHz still be ALOT faster than 448 cores at 1401 MHz ?

I'm really curious about this because i could buy 2 470's for about $150 more than 1 480. and i think evga has overclocking software for their cards too.

thanks

As much as I'd lve to tell you to swing for the 480, I love my 470's. The current system I have uses 2 of them in an expansion box and the motherboard has an onboard video card. I tested this today and was able to have 2 instances of octane open and rendered 2 scenes simultaneously. The onboard video card was great as there was no operating system lag in doing anything. I dont think that the 200+Mhz difference between the 470 and 480 will hurt that much. If you work on scenes that are really big and use large texture maps, you might need the extra 300+ megs of ram. Currently I have not seen a need for this yet in my scenes.
Be very careful about overclocking, or buying overclocked versions of the 470/480. These cards will run hot to start and running them at full throttle for a long period of time could result in some very very bad results. Radiance usually says it might be best to down tune the gpu if they start to get too hot.

thanks !
typically my scenes aren't that large or use very large maps either so i figured having almost a double amount of cores (even if they're a little slower ) will on average render my frames alot faster.

that's good to know about the overclocking, and since overclocking isn't how i earn my paycheck i don't have time (or the interest) to find the right settings based off of whether or not the computer crash's at what setting.

hi i am thinking to upgrade my hardware should i go for 480GTX or Quadro Fx 1800? Suggestions please

@franklau : we can't know what are your needs beside Octane, so some of your other applications may require some specific features of the Quadro FX 1800. You are the only one able to know that, but for Octane and ordinary applications, I would chose a GTX 480 without any doubt :

It has 480 cores instead of 64 on the Quadro FX 1800, and 1536 MB of memory instead of 768 on the Quadro FX 1800, and they are currently sold at almost the same price.

For my own, as I use currently a 8800 GTS 512 with 128 cores (one of the weakests cards usable with Octane), I wouldn't want to change for a more expensive card with only 64 core, even if someone would offer it to me !

I'm almost sure that you will never be able to render animations with a Quadro FX 1800, and I fear that you will have to shave your beard several times while waiting for a single render of a still image !

Quadro FX 1800 specifications here :

http://www-307.ibm.com/pc/support/site. ... 72635.html

Geforce GTX 480 here :

http://www.nvidia.fr/object/product_gef ... 80_fr.html

@franklau I upgraded to a 480 GTX from my old 8800GT this weekend, and it's amazing. You will not be disappointed by the 480 card. Also, many people complain about the noise level of the 480 cards. I can't see what the fuzz is about, when idle and under normal load the 480 makes slightly more noise than my old 8800GT. And on full load the 480 makes less noise than an XBOX 360

I want to buy two 480 gtx, I wonder if the octane will use the 960 cres available, I already know that only one memory will be used, but I wonder if in terms of performance will be twice as fast?

I really need to know it! I will buy it tomorrow!

cya!

Elvio wrote:I want to buy two 480 gtx, I wonder if the octane will use the 960 cres available, I already know that only one memory will be used, but I wonder if in terms of performance will be twice as fast?

I really need to know it! I will buy it tomorrow!

cya!

Yes, it is 1.8~1.9 times faster.