OTOY Forums

Hello Octaners!

I just installed the demo version on my Mac Pro 3.1, running off a Quadro4000 with 48gb of ram, Yosemite os. I used the plugin for Cinema 4D to run Octane, and I was kinda underwhelmed by how slow it rendered!

So if you have some pointers for me that would be great! I read somewhere that the Mac Pro 3.1's PCI bus is just too slow. Or do I need one more card, or just another card?
I'm not looking into building a water cooled Titan render machine just yet, I'd like to see significant speed boosts using Octane before I commit.

Thank you!
Urt

hi,
firstly, it must to be said that, natively, the Mac Pro can handle only cards with max 6+6 pin power connectors, so if you want to add a GTX 980 ti or a Titan, you need an external PSU for powering the cards.
the Quadro 4000 has an average score of 21 while a GTX 970 has an average score of 80 (roughly 4x faster). You could use the Quadro 4000 for display only and add a second GPU just for Octane, but you need an external PSU, because the Quadro needs a 6 pin connector.
This is always the best setup. Otherwise, you could just switch from the Quadro to a more powerful GTX with max 6+6 pin connectors and use the render priority option.
ciao beppe

I came from Cinema/Vray on a Mac Pro 5.1 and there are pros and cons with Octane IME. For some jobs there is a huge benefit in production speed, and I actually did a few jobs with it while I was still evaluating whether to invest in dedicated hardware. But it depends where you would like to see that speed increase that would dictate if Octane was beneficial for you.

On very large-scale scenes with lots of geometry I find vray to be better. Its also a much more mature plugin. But lighting can be very generic-looking.

On small to medium scale jobs that are lighting-critical Octane is better because of the realtime feedback. I could be doing something wrong but this becomes less productive the heavier the scene (because I do lighting in parallel with scene setup and shader development - each time you change something it has to resend the scene or part of it).

For refraction-heavy scenes Octane is also a no-brainer compared to vray. Ditto if you don't want to have to fuss with GI settings.

The crucial benefit for me though is that lighting is simply looks better on most scenes. It takes a fraction of the time to get a non-generic, high-quality lighting feel in Octane than any other renderer I've used.

Just buy an external PSU, they're cheap, and buy the fastest card you can afford. GTX 980 has a lot of bang for the buck for a 4GB card. Note that if doing high-res print you'll want a 12GB card, like the Titan X. Until v3, which will be able to use system RAM for frame buffer I believe. For animation its less of an issue.

Thank you for the tips!

Actually I was wrong, I have the 4.1 if that makes any difference?

So Beppe, what you're saying is basically to go for the GTX 980? Like this one http://www.macvidcards.com/store/p42/Nv ... _4_GB.html
In the description it says that no additional power supply is needed, but that's only if I remove the Quadro400 right? And then use the power pin for the gtx instead, and that would still give me a speed boost?

Do you Bepper or Sdanaher have any good technique at hand on how to properly install an external PSU, or to mod the internal PSU to deliver more juice? If that's at all possible on the 4.1?

Thank you again!

I'd also like to ask you if you recommend the GTX980 before the Titan 6gb? (Not the Titan X). They're both about the same price.

Thanks!

On my 5.1 there are two mini 6 pin power sockets on the board that can power one card with the right adapter cables. My Mac Pro came with them for its ATI card. I also have an 8-core MP that I think is a 4.1 and that has 2x 6pin sockets too. You can power 1 GTX 980 directly from the MP, I think. BUT if you like octane you *will* want more cards and for that you need more power. The external PSUs are not difficult to set up. I feed the cables in through the spare PCI aperture and I have 2 Titan X's stuffed in there. You also need to jumper the pin on the PSU so it starts up without being connected to a motherboard. The PSU sits on top of the mac, is very quiet and comes with a nice selection of sheathed adapter cables (6 pin, 4 pin etc)

http://www.amazon.co.uk/gp/product/B00L ... ge_o00_s00

However these cards do get hot so I'm looking for an external PCI solution so my MP does get roasted.

Macurt wrote:I'd also like to ask you if you recommend the GTX980 before the Titan 6gb? (Not the Titan X). They're both about the same price.

Thanks!

I used gpuboss.com to compare cards. Eg the 980 is as fast for all practical purposes as the titan x 12gb but has less vram.

Sdanher, thank you for your reply!

Since I'd like to still use my Quadro4000, I guess I need to get an external PSU then so I can run both at the same time.

Just curios: if the gtx980 is as good as the TitanX, why don't you run two of those instead of the expensive TitanX's?

/
Urt

hi,
please, use OctaneBench for evaluation of different GPUs, as you can see the titan X has an average score of 128 against 98 of a GTX 980 and you have 3x VRAM
For the external PSU, look at this video from Corsair about the paper-clip trick

ciao beppe

I read you thought about getting a card from MacVidcards. I'm sure they are good, but they're also more expensive than PC cards. I only use out-of-the-box PC cards in my MacPro 3.1, with external PSU's, and apart from the boot screen which doesn't show (the very first one with apple logo, not the one you have to type your password of course) I never experienced any incompatibility problem.