ASRock z97 extreme9 cannot fit more than one GTX1080ti

sciencefans

Prominent
Aug 13, 2017
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I updated the latest BIOS version, inserted 2/3/4 msi GTX1080ti, and entered the system (win10) with latest NVIDIA driver(384.xx), then after a few seconds, the screen froze and the fans of all GPU cards squealed. Finally I got a BSOD.
However if I insert only one GTX1080ti, everything goes fun. And if I insert 4 TITAN black, nothing wrong happens.
Could anyone give me some advice?