Because there is no ATX supply, the 100 ms begins counting when the 3.3V and 12 V system supplies reach within 9% and 8% of their nominal voltages, respectively (see the PCI Express Card Electromechanical Specification ).
50 ms (T POR ) + 33.2 ms (bitstream time) + 2 ms (ramp time) = 85.2 ms
85.2 ms < 100 ms PCIe standard (okay)
In this case, the margin is 14.8 ms.