9.1-RC3 IGB dropping connections.

[Zaphod Beeblebrox]

I've got an Intel server motherboard with 4x igb (and 1x em) on it.
The motherboard in question is the S3420GPRX and the IGB's show up as:

igb0: <Intel(R) PRO/1000 Network Connection version - 2.3.4> port
0x3020-0x303f mem 0xb1b20000-0xb1b3ffff,0xb1bc4000-0xb1bc7fff irq 19
at device 0.0 on pci3
igb0: Using MSIX interrupts with 9 vectors
igb0: Ethernet address: 00:1e:67:3a:d5:40
igb0: Bound queue 0 to cpu 0
igb0: Bound queue 1 to cpu 1
igb0: Bound queue 2 to cpu 2
igb0: Bound queue 3 to cpu 3
igb0: Bound queue 4 to cpu 4
igb0: Bound queue 5 to cpu 5
igb0: Bound queue 6 to cpu 6
igb0: Bound queue 7 to cpu 7

... now... I have this machine (right now) on the local lan with my
windows 7 workstation and putty sees the ssh connection as dropped
often.  I say often --- in that it can happen in a minute or two... it
often seems to happen when there is active output going to the window
(like a download counter running), but I also say "often" in that...
it seems slightly random... but it _is_ incessant... as in very
"often."

This seems like something that we should ship with 9.1...