Is Cycles able to run simultaneously an internal and an external GPU?
Hi everyone, it's been a while that i'm planning to upgrade my hardware, the idea was to buy a notebook because of the need to have something that I can bring with me wherever I need. Beside of that, I would love to have the opportunity to upgrade it with an eGpu in the future to be able to take advantage of all the power I could have at "home" but at the same time be able to have a nice machine on the go. So my question is: What if I buy a notebook with a pretty decent internal GPU and then I'll associate a sister of the same but External? For instance a Notebook with this specs:
RTX 2070 Max-Q 8G, i7-8750H, 16GB DDR4, 512GB NVMe SSD
associated with an
RTX 2070 eGPU
Will Cycles be able to use both of Graphic cards simultaneously?
I read a bunch of articles that discourage the use of eGpu due to the degradation and the slow down of the signal through the Thunderbolt 3 port, but everyone considered the "gaming side" of it.
Should I expect the same problem with cycles?
Can someone help me? Is there someone that has experience with this kind of stuff?
Thank you all,
Guido
6 Comments
I believe the biggest reason for slow down in using a eGPU in a AAA game would be because in a video game the cpu is required to build instructions and transmit those instructions to the gpu in real time. Where as I believe in blender the instructions would be transmitted around less often. (once per frame rendered?) Therefor I do not believe the decrease would be as much as a real time game or render.
* @tony balonie * Hi Tony,thank you for your response, Yes that's what I thought as well. I think that the bottleneck in the use of an eGpu for gaming is the slowdown during the transmission of the data back and forth between the pc and the external graphic card. Not for nothing, I heard that to be able to take the best advantages from the eGpu it would be better to use it with an external monitor so that all the information must not to return again to te pc. What about the simultaneous use of the internal and external gpu in conjunction? Do you think that would be possible to use them together for the rendering? Or then I will have to choose between one of the two?
* @Guido-Medici * I am less confident in my ability to answer the question related directly to blender support. You mentioned that it would be connected through a thunderbolt 3 port and I believe it would depends on the software making the connection, which might vary between docking stations for all I know. If the operating system itself recognizes the eGPU in the same way as a normal GPU then I see no reason why it would not work. But I would wait for someone to confirm that, I am no expert.
Also I said above that it wouldn't be as slow as in gaming, however you should still expect to see some performance loss. You mention in the post that you are more interested in future use of a external GPU. Keep in mind that by the time that future point comes around there could be better technology out which may be faster AND cheaper. Ultimately trying to get a lot of power in a laptop is going to be pricey. You might be better off building a strong tower computer, and then having a mid level laptop to remotely connect to the tower with. Now I'm just giving opinion though :)
* @tony balonie * Thank you Tony, I really appreciate your suggestions. Now let's see if there is someone that has some direct experience with this kind of configuration and with Blender.
better place to ask such questions is here devtalk.blender.org/ . there are devs of cycles itself - nobody not tell you better about cycles than they
* @Bo Shi * Thank you Bo Shi, I will try