As part of the great Christmas holiday tradition of fixing the family's computers, I've been looking at a weird issue with the younger brother's PC. Occasionally it will crash in such a way that it's NIC floods the network with junk data in such a way that the entire local Ethernet fails (even pinging other hosts showed over 80% packet loss).

Unfortunately I've not been able to capture exactly what it's sending - directly attaching my laptop shows a huge number of bytes being received, but they don't propagate up the stack far enough to be captured with Wireshark. I'm guessing it's just spewing noise, but it doesn't seem to be affecting the rx_err count (though it does hive a large number of rx_mac_pause/rx_64_byte_packets).

Current solution seems to be reset the PC and everything is good, though I'd be curious to see exactly what it was sending that could trash all network connectivity. Maybe time to go Google the network card details...

tried it with a live cd to rule out the os/software?

It would be a good idea if it were more reproducible. So far it's only happened once in the two weeks I've been back home. I was meaning to go digging through the crash logs to see if it gives any clues why the system hung - would be great if it was crashing 3 times a day like family said it was.