Multi GPU setup

[aliwalker]

I have an RTX2080ti card and looking to add a second RTX card to speed renders up. Would adding a RTX2060 actually slow the renders down due to the 2080ti being faster? Would memory allocation be set to the card with the lowest GPU memory or would it take the card with the most? I believe it only uses both with Nvink

[Stephen.Blair]

Check GPU FAQ, it covers this: https://docs.arnoldrenderer.com/x/7o0sBQ

[aliwalker]

Thanks Stephen, I did read that but found the bit about mixing lower/higher spec GPUS a bit vague

" One possible limitation of using differing RTX GPUs at render time is that the less powerful GPU may end up throttling the more powerful one as the work is divided between the GPUs evenly "

Is this therefore an actual limitation? What happens to memory too when not using NVlink? Does it take the higher spec GPU memory or cut it to the lower GPU memory ?

[thiago.ize]

Essentially combining a 2060 with a 2080ti should roughly behave as if you had two 2060s.