Description
No, VCCL_GXB does not need to be powered when transceivers are not being used in Arria V GX/GT devices. The Arria V GX/GT Datasheet and Pin Connection Guidelines refers to these power pins being used for clock network power. They are used for the transceiver clock network only.
Resolution
A future version of the Arria V GX/GT Datasheet and Pin Connection Guidelines will update the VCCL_GXB description.