When Aurora 8B10B is targeting Artix-7 GTP and Virtex-7 GTH, the simulation is slower.
This answer record explains why this occurs.
This reset sequence requires the SIM_RESET_SPEEDUP attribute of the GT simulation model to be set to FALSE for proper functionality in simulation.
This emulates hardware reset behavior in detail and causes the simulation to be run for longer.
08/04/2014 - Initial Release