ASUS P9X79 PRO

[Ryste3d]

Hi,

Could somebody please help me to get the most out of my ASUS P9X79 PRO motherboard.

I am new to Octane and are trying to figure out my best setup for Octane Render.

How many Graphic cards (ASUS, GIGABYTE, EVGA etc.) can I install on this motherboard to get the best performance with Octane?

I already have one ASUS GTX 680 2 GB

Thanks

[pixelrush]

Well assuming you put your 680 in the first slot you could put another 680 in the 4th one if your case will allow it and then its a matter of what you do with the other 2 slots. If you want to max out the potential you could put another 680 on a pci-e riser in the 2nd and put a single slot basic card in the 3rd dedicated to display, assuming you can set which slot to use initially in the BIOS, usually you can. You would need to make some creative case support for the one on the riser and be sure to get a psu with 6x 6/8pins. Something like 1200 w I suppose.
If you can't fit a dual width card in the 4 the slot because of the case you will need to put your single slot display card there and use 2 risers for the 680's. Having a dedicated display card would be the most responsive combo though.
If you don't want to do risers then 3x680 will have to do. It would be better if you had got a 4gb 680 for this situation because some of the vram will be used by the system.
Perhaps you could buy another 2 gb and one 4gb with the intention of using that in dual duty as the display and for rendering. Honestly I am not sure if it can work exclusively for the display like that though. I suppose it can if you nominate the 4gb one in the BIOS as the initial one and have it active in Octane?? Perhaps someone else can advise you there but that combo effectively gives you 3x680/2gb for rendering and it all fits easily.
If you wanted the max performance with least issues you could persist with the 680 you have but use that as a display card and get 2x690 for Octane assuming your case will take long cards. You might need even more watts psu and make sure each rail can provide enough current for the 690s. That gives you effectively 4x680/2gb for rendering or maybe you can use all 5 sometimes if your scenes are smallish?
Dunno really I guess it comes down to how much you want to spend and how badly you want to max out the mobo and what fits or can be creatively accomodated. You need to pay attention to cooling as well with a lot of closely spaced cards...
HTH
Other forum readers might have better or different ideas for you.

Edit: here is a pic of the mobo for others to view

[Ryste3d]

Thanks pixelrush,

I will now order 2xGTX 690, a CORSAIR AX 1200W PSU and use my old 680 2GB for display and rendering.

Du you know the speed for this setup for the OCTANE BENCHMARK?

I would love something around 20 Ms/sec or am I dreaming? (16)

I already have a GTX 680 2GB, a GTX 680 4GB and a GTX 480 but have not tested this since I am waiting for the PCU to arrive.

My question is: how would this compare to the 2x690 + 1x680 2GB?


Again, thank you for explain this to me...

[pixelrush]

At a guess

680+2x690 ~ 17.3

2x690 ~ 14.4

2x680 ~ 7.2
This last combo I left out the 480 because although it can make a fair contribution it has 1.5gb vram. What ever scene you load into Octane the same data is loaded into each card and therefore the card with the least vram determines the max size of the scene. The 4gb of the 680 would be a bit of a waste since either 2 or 2.5 gb would be unused.

A 690 is 2 680 gpu together. Your scenes are limited to 2gb.

[Ryste3d]

Thanks pixelrush, you have been so helpful!