Adding another GPU via Thunderbolt 3 eGPU

[akashi1]

I can out of PCIe slots but I want more rendering power. I use one GPU for display and one dedicated for rendering and im using the last slot for a Thunderbolt_3 card. Can I add an e-gpu and another card for rendering? Would V-Ray see it?

[Micha]

Do you need the Thunderbolt 3 card or do you like to use it because the slot space is to limited for a third GPU?

[akashi1]

I need to for my display.