Error (11686): Your design contains more than two ATX (LC) PLLs in the same HSSI transceiver bank - Error (11686): Your design contains more than two ATX (LC) PLLs in the same HSSI transceiver bank Description You might see the above Fitter error in Quartus® Prime software version 15.1 with Stratix® V and Arria V GZ devices. The reason for the error is because the Quartus Prime software version 15.1 software fails to merge two or more ATX PLLs. Resolution To work around this problem, you can use Quartus Prime software version 15.1.1 or later. Custom Fields values: ['novalue'] Troubleshooting novalue False ['novalue'] ['FPGA Dev Tools Quartus® Prime Software Pro'] 15.1.1 15.1 ['Arria® V GZ FPGA', 'Stratix® V GS FPGA', 'Stratix® V GT FPGA', 'Stratix® V GX FPGA'] ['novalue'] ['novalue'] ['novalue']