LVDS_TX error on too many fanout, but connected to single pin - C10LP

Hi,
the error is caused by ALTLVDS_TX tx_outclock connection. You are using it to drive NCO IP in your design. Honestly I don't understand why, that doesn't seem to make sense because tx_outclock is intended only as a reference for LVDS output signals. Fortunately we don't need to understand the design objective to fix the error.

Problem is that tx_outclock is the output of a DDIO_OUT block rather than a direct PLL clock that can be used internally. If you want access to LVDS_TX fast_clock PLL signal, you need to switch to ALTLVDS_TX external PLL option. Or generate 300 MHz clock with other PLL.

Regards
Frank