Give us a clue. What have you found?
You may want to look at this thread
but I am sot sure it applies to you as your card identifies as an R8139D. There is also this thread
which, if you follow through the link suggests that possibly the wrong driver is being loaded but it does suggest loading the 8139too driver rather than the 8139cp driver but that is what you are doing. What does "lspci -n | grep 1904" give?