Desktop PC with external GPU - USB 3.0 connected
Mazh
Posts: 487
Hi,
seen things like two GPU cards on one MB in one case or external cases for notebooks to run an external GPU instead of the onboard graphics chip, but I'm interested in a flexible solution to make two GPUs work together.
Like running a desktop PC with one 1070/ 1080 8GB GPU and having a second GPU of the same type in an external case, which is only connected when additional graphics power is needed (hugh scenes, animations).
I've seen videos about building crypto mining rigs, and they've connected GPUs in an external case via USB with PCI riser cards to 1x PCI-e slots on the MB.
Does this also work for rendering with DazStudio, so just get an external case with power supply and a riser card with USB 3.0 connection ?
Appreciate any advice or link, or even better, someone who's running exactly that solution and tells me it's works perfectly fine
Thank you
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Comments
An external enclosure will work. It is expensive, you have to buy the box and the card(s). If you have a desktop you can install multiple GPU's in the box. If you exceed your available power and PCIE slots you then need to get into mining rig type setups but you don't need or want an enclosure. You want a few pieces of lumber, PSU's and riser cables.
After my desktop died, I bought a laptop with Thunderbolt 3 and stuck my graphics card in a Sonnet external case connected via Thunderbolt cable, which works well as a single card solution (no nvidia on laptop).
Have considered trying a second card in the case, but not sure it has the space, power or cooling to accomodate. Or may see if I can build a new desktop with a motherboard that supports thundebolt chaining to my egpu, and run second card in desktop instead. Something similar to what OP is considering.
Don’t know whether Thunderbolt vs USB 3 factors in the equation, but yes, if any one else has insight, I too would appreciate it. (And wondering if my old Titan could be run parallel with a non-SLI RTX card.)
@ kenshaw011267
thanks for your answer, I'm not sure if I completely understand.
I have a Desktop PC, but I don't want to put the second GPU into the MB because I like the idea to just connect it when it is needed.
I'd like to use this
https://www.amazon.com/Mining-Express-Adapter-Extension-Ethereum/dp/B079SL7YDW/ref=sr_1_9?crid=135C6DAN0BLYK&keywords=pcie+riser&qid=1569608929&sprefix=pci,aps,251&sr=8-9
to build something like this
Won't work for multiple GPU's unless you buy an enclosure built for such or you can code and burn firmware to handle the PCIE to USB connection between multiple devices.
The way mining rigs work is they use riser cables plugged directly into x1 slots on the motherboard and just house the GPU's and PSU's on some sort of open air rig. And that's an awful lot of messing about to add one GPU.
If you onl;y want to add one just install it in your desktop. When you're not using it it will just sit there idle.
If you want to buy a bunch of 1660's or the like and run them as some sort of dedicated render box then:
Get something like this:
https://www.amazon.com/Aluminum-Mining-Case-Frame-ZCash/dp/B073SMF21G/ref=pd_bxgy_147_img_3/136-4306729-0887323?_encoding=UTF8&pd_rd_i=B073SMF21G&pd_rd_r=cd9459b8-ab03-4c4a-b4aa-3dcfc56c3d46&pd_rd_w=0J9ps&pd_rd_wg=Cjgkm&pf_rd_p=479b6a22-70ae-47a0-9700-731033f96ce8&pf_rd_r=TD79SSJ52SCEFJ71RA4P&psc=1&refRID=TD79SSJ52SCEFJ71RA4P
This:
https://www.amazon.com/B250-MINING-EXPERT-Motherboard-Cryptocurrency/dp/B075KFPJ6M/ref=pd_cp_147_3/136-4306729-0887323?_encoding=UTF8&pd_rd_i=B075KFPJ6M&pd_rd_r=93201cd4-b09d-4ff5-bfea-7a2e2caa174e&pd_rd_w=nF063&pd_rd_wg=LPOcZ&pf_rd_p=ef4dc990-a9ca-4945-ae0b-f8d549198ed6&pf_rd_r=ZPFS7X5PX694697QKSMY&psc=1&refRID=ZPFS7X5PX694697QKSMY
And this:
https://www.amazon.com/Intel-i7-7700K-Desktop-Processor-unlocked/dp/B01MXSI216/ref=sr_1_2?keywords=i7+7700&qid=1569614896&s=electronics&sr=1-2
Which should support up to 8 GPU's for iRay rendering. You'll need a couple of decent PSU's (wattage won't have to be super high but get the best 80+ rating you can as drawing this much power enough to make rig like this worth the cost will hit your power bill so efficiency matters.)
I second the motion of putting your GPU into your computer case and not into an external case, especially if you've only got one or two GPU cards. Keep it simple, silly!
And there's another reason to NOT be messing around with this kind of a setup. "Connecting and Disconnecting" a GPU manually/physically will increase the risk of damage to the card, motherboard, and cable components and connections. Anything from a clumsy thumb breaking off a capacitor or connection tab, to an unlucky day where you inadvertently zap your card or motherboard because you were carrying a little more electricity with you after petting the cat or walking on the carpet.
Your plan may sound clever, but this would basically be "a tweak". Stop teaking, people; you'll do more harm than good! There, I said it.
Thanks for your answers.
I've thought I haven't described my plan that bad, but I can try to get a little bit into details.
I've planned to:
1. Buy one of these riser cables I've posted earlier, price < $10
2. Buy an used desktop case with PSU, price < $10
3. Since the mining hype is over, try to get an used mining GPU for a good price, maybe from a vendor with limited warranty, price ~ $100
4. Build it exactly mining rig style (with the option to connect/ disconnect the rig as needed, for power consumption reasons - my actual GPU is good for the most rendering tasks, except hugh scenes and animations), and -
5. if it works out well, have the the option to repeat step 1. + 3. once/ twice more.
And of course I've never planned anything like connecting/ disconnecting GPU cards as needed (since there are USB connectors on the riser circuit boards to do this), where did I write that ?
I would even build a solution to keep the USB connectors on the riser circuit boards (the cute 1x and the big 16x) free from connecting/ disconnecting stress.
But to follow your advice and keep it simple, I take back my original question and ask the following instead:
Does a mining rig works exactly as a render rig for DazStudio/ is DazStudio capable to use a mining rig for rendering - and I guess this is already answered by kenshaw011267.
I apologize for sharing my thoughts and reasons with you.
I
I did what your looking to do. I had this system built originally for 2 980ti's. 4 or 5 years ago. but have since upgraded a lot of things to add to the performance so my system specs have changed greatly over the years and why you would like a system like this for the massive upgrades you can do
currently I am running 2 evga gtx 1080ti - 11.9 gig GPU in a USB.30 VisionTek - 6 slot GPU Accelerator box I bought a long while back it will hold up to 6 dual slotted PCI.02 and PCI.03 gpu cards and i alo bought the farm and got the EVGA glycol-cooling system with a 120 mm radiator for the gpu box to keep everything cool and quiet down the noise replacing the 6 -120 mm fans , I'm not sure if you can even get them any more https://www.bestbuy.com/site/visiontek-thunderbolt-3-egfx-external-graphics-accelerator-enclosure/6163995.p?skuId=6163995
I run 2 - 29" Samsung ruby LED screen displays on a single gtx 970sc 4 gig internal gpu and use the the external gpu box with the 2- 1080ti's to run my programs & games ,But I will tell you upfront this is not something i plug in and unplug when ever i want to its actually became part of my system proper . and when it messes up its take help trouble shooting it.
I paid geek squad to come out to my house and set this all up after i had researched & I order most of the parts and other stuff from either best buy, EVGA.com or iBUYpower.com . I also invested in a 3500 watt APC Uninterrupted power supply with a emergency battery back up to drive everything , so worth the money. and I have had the geek guys come 3 or 4 times since for tuning and fixing things that have broke or burned up lol
lastly I kept adding ram chips and upgrading them until i have my system maxed out at 124 gigs of system Memory this is a picture of my set up in my home office
I posted my system specs . which is found by typing in your start menu system information
my systems getting old now it was a rocket ship back in the day. So I will properly need to re do this whole systems when windows stops support for windows server on windows 7 :(
But what your looking to do can be done and yes it is expensive and i would recommend paying for someone to set it up for you that knows how to its so worth it just to save the frustration. and with the new RTX GPU and the silicon 2x 24 core processors .you properly could build even better cheaper than I did
I hope that helps with your decision :)
@Ivy
Thanks a lot for your detailed answer
Originally I'm aiming for a cheaper and self made solution, but it is nice to see that a professional setup for this exists.
I mean, it can work, but why? If you are talking about just using a second GPU, why not stick in the case you have? The only consideration here is that you have enough room for proper cooling, and a PSU that can handle the job. You would still need a good PSU regardless.
Going the enclosure route is fine, but it also involves additional risk. I think I read in the forums somewhere that Daz staff burned up a GPU testing out enclosures. I don't know if that was just gossip or something that actually happened, but it is a risk you take. You mentioned that would not just be unplugging the card and stuff, but if that's the case, the card would would still run just like it would inside the case. If the card is plugged up, it will power up, simple as that. It may not be actively doing anything, but it will be powered up idle, it doesn't matter if it is inside the case in the motherboard or hooked up through USB it will power up the same. So you wouldn't be saving anything using USB. Oh, and since you would be using USB (or whatever, doesn't matter) this provides another possible failure point.
Think of it this way, the more complicated you make things, the more complications you can have. I do not see any benefit in this if you are only adding a 2nd GPU.
If you want to run a bunch of cards, then a mining rig can do the job. But if you just want 2 cards, your case is fine.
I have two 1080tis. I only use both when rendering, even though I could do SLI for gaming. These are big cards, especially that fat 2.5 slot MSI, but my temps stay reasonable rendering Iray, the top card may hit 74C, the bottom card may hit 64C.
for me the essential out lay was a killa , but after having it for so many years its paid for it self 100 x over. a PC custom home built for, max performance, hard use and ease of upgrading components . if it were not for the fact windows server support is going to expire soon for window 7 pro I would keept upgrading this system but you know how that is you. finely get a bed perfect just the way you like it, and poof someone comes along moves the blankets and pillows.