I'm using 16bit 3c509 cards (ep driver) on some older 386s.
   On one machine, I have 211 Ierrs to 58462 Ipkts.  This machine nfs
   mounts directories from the other.

Keep in mind that the original 509 had only a 2k buffer.  On a crusty
386, it's entirely possible that the next packet just came in too
quickly and overran the buffer before the CPU could catch up.