ID:167046 Can't place GXB refclk pre-divider, central clock divider or transmitter local clock divider atom "<name>"

CAUSE: The Fitter cannot find a legal location on the device to place the specified gigabit transceiver block (GXB) refclk pre-divider, central clock divider or transmitter local clock divider atom.

ACTION: Remove or modify location assignments and/or I/O standard assignments of the related pins feeding the related atoms.