This Gauge32 holds the highest single-sample count of PCIe ERR_FATAL messages that UCS Manager observed during any one collection interval within the last hour, i.e. the link partner signalled an unrecoverable (fatal) PCIe error condition over the ERR_FATAL sideband message, captured at its worst moment. Unlike the plain (non-H) gauge for this window, this high-water value stays latched at the worst reading for the rest of the window even if the fault stops recurring, which is what lets an admin catch a brief PCIe error burst that a simple end-of-window snapshot would have missed. For example, if a marginal riser produced a spike of 7 PCIe ERR_FATAL messages in one polling cycle and then went quiet, this field would hold 7 until the last hour window rolls forward, even though the plain gauge has since dropped to 0.