I just received my x98 pro dual boot yesterday, seems like mine too has bricked. I was using windows at the time, and suddenly the screen blacked off. I tried to turn it on but it didnt and also tried it with the vol buttons but no progress -.-
I saw a couple of queries posted here and there regarding this issue but solution was nowhere to be found 🙁
I hope we find it soon.
ps changing cable did not help