Hello to all! I'm hoping someone would be able to help me with a technical issue I seem to be stumped by.

I'm running an I7-6800k, 2 1070's in SLI on the Ultra Gaming X99 motherboard on latest bios (also have nvme ssd installed). I recently purchased the Alpine Ridge Thunderbolt 3 (Revision 2.0) pcie card. I installed it in x8_1 pcie slot. Upon booting, I noticed my sli configuration is gone. As I understand the motherboard manual, because slots x16_1 and x8_1 share pcie lanes, x16_1 should drop to x8 if x8_1 slot is occupied, correct? Am I just running short of PCIE lanes with this set-up? Before I return the card, I thought I'd reach out. Thanks!