I've had this problem too on using an Asus P7P55D-E LX motherboard with Realtek RTL8111, a Core i5 processor, and an Nvidia GTX460 graphics card. After exchanging every single component except the CPU, graphics card, and memory sticks, ethernet now mostly behaves decently but I still have the freezing problems mentioned by some above. Ive reported those separately as bug #720863. It would be good if people with the same problem could check out that bug and add yourself as affected or otherwise give feedback because nothing seems to happen.
I've had this problem too on using an Asus P7P55D-E LX motherboard with Realtek RTL8111, a Core i5 processor, and an Nvidia GTX460 graphics card. After exchanging every single component except the CPU, graphics card, and memory sticks, ethernet now mostly behaves decently but I still have the freezing problems mentioned by some above. Ive reported those separately as bug #720863. It would be good if people with the same problem could check out that bug and add yourself as affected or otherwise give feedback because nothing seems to happen.