Can I connect unused GXB_REFCLK pins directly to GND in Cyclone® V GX devices?

Description

Yes, you can connect unused GXB_REFCLK pins directly to GND in Cyclone® V GX. This is indicated in the Cyclone® V Pin Connection Guidelines. However, a Quartus® II generated .pin file for this family indicates that an unused GXB_REFCLK pin should be connected to GXB_GND* (pulldown via a 10K ohm resistor). 

Resolution

This is a bug in the Quartus® II software and will be fixed in a future release.