NI PCIe-8372

Hi

I'm pretty much lost as where to post this question, but this looks to be the closest forum.

I have a PCIe-8372 4-lane cablePCIe PCIexpress card. It is connected via cable to custom hardware. When operating in 4-lane mode the system (NI board, cable, and our custom board) work fine.

If we lower the lane width to x1 on our board (simple FPGA re-programming), then the host PC will not 'see' our hardware and the PCI-8372 does not even attempt to negotiate a connection.

Is this normal behavior? Must the 8372 always be operated in x4 mode?

Thanks.