That can happen. That's a shame.I've seen a few Zotac cards do that.Problem is that the 780 Ti BIOS usually has a lot more options to play with, but the Zotac 780 TI has quite a few less than usual. In fact, it mimics the normal 780 BIOS. I think that's the reason for incompatibility and I don't know why Zotac used slightly modified 780 BIOS for their 780 Ti cards. Other vendors use their own custom BIOS that's much closer to reference 780 Ti's BIOS.