Intel 7260 PCIe + S1200BTS Server Board = Not working

Hello,

when i install the Intel 7260 PCIe WiFi Card into my S1200BTS Server Board the card is detected and working. As soon as i install other PCIe Cards alongside with the Intel 7260 Card only the Intel 7260 Card will be detected. All other Cards will not be usable or visible. Intel support says this is because the 7260 PCIe is only designed for Desktop Boards. I wonder how this is even possible since PCIe seems to be a standard and every other Card i plug into this Server Board also works without problems.

Is there any method to workaround this?

Thanks