Actually i have two 3090 and one 1080ti.
I use 3090s for render purpose and to make the cooling of this cards more efficient i put them in a separate container and connected to my computer with pci extension cluster. Here is a devise that i use https://www.amfeltec.com/multi-gpu-cluster/
1080ti i use only to connect 3 monitors together. If i sell 1080 ti my render rig will not be efficient enough.
I also want to use 3090 for UE4. I found out how to choos the GPU in my nvidia control pannel but now i faced with another problem. UE4 crashes after i starting my file. But if i back my 1080ti GPU, the file works fine again.
What can be the reason of that crashed?