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Hi guys,

I just wanted to share my experience regarding external GPU usage in C4D/Octane. I've been looking into it for a little while now and have seen a few very helpful posts from Smicha and Tom Glimps (big shout out to you guys) before actually deciding to invest the money. The solution I bought isn't water cooled and admittedly is rather expensive, but since I have no idea about the technical side of things I decided to go with something out of the box. So I went ahead and bought the Netstor NA250A, which is a fan cooled box powering four slots for dual slot graphic cards. it has got a 1000W PSU und you connect it via a PCIe card with your PC. I am running a GTX 980 Ti internally within my PC and put my two previously bought GTX 970's plus another two GTX 980 Ti's inside the expander.

So far I am very happy with the performance. After running the Octane Bench test three times I each time got a score of around 510. The 980 Ti's are getting pretty hot when running on full steam, around 77 to 80 degrees celsius, which I read is quite normal during long gaming sessions anyways, whereas the 970s stay stable at around 60-62 degrees. This produces a lot of heat coming out of the backside of the box, which is nice during winter time The noise of the fans, however, is something I find quite annoying when I am running the expander the whole day. I ended up just switching it on just when needed, to a) to minimise power consumption and b) having a quieter working environment.

Btw, I upgraded to Windows 10 a few days ago and as far as I can tell C4D and Octane are running smooth and stable.

Here is a photo of this little beast.
The setup itself is fairly easy, pretty much plug and play. Put the GPUs in their dedicated slots, attach provided power cables, install the PCIe card in your PC and connect PC and expander with the two provided cables, voila. However, I've had a few issues in the beginning. For whatever reason one of the slots within the expander didn't recognise one of the 980 Ti's so I had to switch cards about 7 times until I've found a order both, the expander and my PC were happy to recognise. Following that my monitor started flashing to black, which was solved by reinstalling the graphic cards driver. Since I haven't had any issues and are still blown away by the quality and speed Octane render produces - especially with this extra GPU power.

If anybody out there is thinking about buying more render power as well and has some more questions just ask and I am happy to answer if it is within my knowledge. Remember, I am not a technical person

Best
Dan

$ ?

RobSteady wrote:$ ?

Nicely articulated question! Nevertheless very import, I forgot to mention that.

The expander itself comes at around £1390 and the there 980 Ti's at around £500 each excluding VAT.

Those prizes....

What crazy type of adapter is in it for it to be so expensive?
I think the upgrade-ablilty/expansion-option is just worth so much? Probably niche market anyway

The idea behind the expander is great...but you can buy a really nice workstation for this price.
With an i7-5930K, mainboard with 4x PCIe x16, 32 gb ram, 1200W quality psu, ssd, big tower case with good cooling, windows and dvd drive.

If you find a good reseller, you will have some money left to buy another Octane license so you can use this machine as a slave/workstation...

RobSteady wrote:The idea behind the expander is great...but you can buy a really nice workstation for this price.
With an i7-5930K, mainboard with 4x PCIe x16, 32 gb ram, 1200W quality psu, ssd, big tower case with good cooling, windows and dvd drive.

If you find a good reseller, you will have some money left to buy another Octane license so you can use this machine as a slave/workstation...

I totally agree that this is a very expensive peripheral and yes, you could buy a powerful workstation for that money but this is not what I am after. I need pure render power for the work I do and another workstation wouldn't give me that - especially considering that there is no option to outsource renderings externally as yet. so for my purposes this is a pretty powerful little render farm I do not need to buy extra licenses for.

Wow, awesome setup dbalzer. Thanks for sharing your experiences. So if I'm understanding correctly, this whole box has a PCIe cable that plugs into a PCIe slot in your main PC? Curious if there's any potential for bottleneck with bandwidth to all the cards going through one PCIe slot on the pc...

I would love to do something like this, but for a macbook pro. I have to look into this more. The dream for me is still having the ability to go anywhere with my laptop in a backpack, and a mini render-farm in a brief-case.

dotcommer wrote:Wow, awesome setup dbalzer. Thanks for sharing your experiences. So if I'm understanding correctly, this whole box has a PCIe cable that plugs into a PCIe slot in your main PC? Curious if there's any potential for bottleneck with bandwidth to all the cards going through one PCIe slot on the pc...

I would love to do something like this, but for a macbook pro. I have to look into this more. The dream for me is still having the ability to go anywhere with my laptop in a backpack, and a mini render-farm in a brief-case.

Hi Dotcommer,
You nailed it! That is exactly what I am doing, whenever there is a big job I need to work on site for I can take the box with me and plug it into either my or another workstation.

And yes, it works with PCIe cables (there are two) going into one PCIe slot on the PC's main board.

As far as Mac Books are concerned I know that there are a few limitations. First of all Yosemite doesn't support more than one external GPU, only older versions of OS X do. And what is important is that your CPU has enough lanes left to support x16 bandwidth coming in from the cables. My PC for instance has a CPU with 40 lanes, 16 are used by the internal GPU, 16 by the expander and the rest for USB and what not. Don't know how that works with Laptops. But I think its worth reading into it, hope you will find a good solution for yourself.

Hi Dan, thanks for posting about this - I've been looking into this sort of gear. The market for PCIe expansion seems split between expensive solutions such as this and the more "derelicte" open air chassis, like mining rigs etc.

A couple of questions - first, how many dual height cards can the case fit? And can you upgrade the power supply? Last question, if possible could you take a photo or 2 of the back showing how it connects to your PC? I've seen some that require riser cards and cables snaking in and out of cases, but this looks a lot neater.

I work in a shared office so I couldn't have an insane cable monster machine sitting near my desk, would be a bit weird.

Thanks!

grain wrote:Hi Dan, thanks for posting about this - I've been looking into this sort of gear. The market for PCIe expansion seems split between expensive solutions such as this and the more "derelicte" open air chassis, like mining rigs etc.

A couple of questions - first, how many dual height cards can the case fit? And can you upgrade the power supply? Last question, if possible could you take a photo or 2 of the back showing how it connects to your PC? I've seen some that require riser cards and cables snaking in and out of cases, but this looks a lot neater.

I work in a shared office so I couldn't have an insane cable monster machine sitting near my desk, would be a bit weird.

Thanks!

Hi Grain,
Answering your questions to begin with, the case can house 4 dual slot GPU's. I am not to sure about upgrading the power supply unit as it fits very neatly in the case. There are other manufacturers offering ready to go cases with 1500W PSU's but as I wasn't planning on getting Titan Z's anyways so I figured that's enough for me. Regarding your cable question, there is only the power cable and the two connector cables between expander and PC:

I mainly went for the more expensive options a because it is vital to me to have something I can quickly grab and set it up in a different office as my work requires this. Otherwise I would have looked into WC but those systems don't travel well