I have this problem after upgrading to Oneiric with an Intel Advanced-N 6200 wifi card. I seem to have temporarily fixed the problem by adding this line to /etc/modprobe.d/intel-6200.conf:
options iwlagn 11n_disable=1 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/836250 Title: [Oneiric] Intel Corporation Centrino Ultimate-N 6300 poor networking, packet loss and very slow Lenovo X201 and T500 laptops To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/836250/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs