Mixing Gigabit, Copper, and Linux

iampgray writes: "With copper-based gigabit cards selling for less than $36 these days, what kind of performance can you expect -- especially in the often-overlooked Linux market? We sought out to test exactly what you could expect from copper-based gigabit solutoins for the desktop interface through the cluster-targeted products. Name brands and off-brands were put through the wringer. How'd they fare? Interesting results to say the least."