This Counter32 is a free-running, cumulative tally of PCIe receiver buffer overflow errors recorded against this PCIe endpoint's receive path since the counter was last reset by a reboot or reseat; concretely, incoming PCIe traffic arrived faster than the receive buffer on this component could drain it. Because it never wraps back to zero on its own, an admin uses it as the lifetime baseline against which the 15-minute/hourly/daily/weekly gauges on this same row are compared to spot fresh activity. A blade that shipped with this counter at 0 and now reads 187 has accumulated 187 such faults since it was last powered up, which on a healthy riser should stay at 0.