Hello,
I have an R810 running ESXi 5.5 that locked up and showed an E171F error on the display. I pulled both risers and reseated them, removed both PCI cards on the risers. A little while later it locked again. I booted into Diagnostics and the memory tests came back clean, but the hardware tests came back with:
System Firmware:: Critical interrupt sensor (PCIE Fatal Err) Bus Fatal Error.
Any help is greatly appreciated!