Possible bad factory assembly of the heatsink/themal compound used.
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wonder if that has to do with some NICs offloading more work to your CPU than others.
Thanks very much for the ideas, Ara!!
I'll have a close look at the heat-sink.
Also, you wondered if the problem has to do with some NICs offloading more work to the CPU than others. I'm wondering about this with some concern - even if it were true, surely the state of the art Intel Quad core CPU should be able to handle a few extra cycles from the nic? Is it really feasible that the CPU would fail in this scenario?
Darryl Gittins