As of today, September 14th, 2011, the jme driver for the JMC2x0 line of NICs is not up to date with the release by JMicron, and this seems to result in the NIC only managing about 10 megabits-per-second, instead of the gigabit speeds that it should. The resolution to this is slightly more than updating the driver, but the other steps aren’t something the average user will figure out on their own.