lol well...i dont really know why. it just is. the same way my 3600 will probably overclock better than a 4800. all of the research that i have done into optys suggests that the 165 just gets easier clocks with less voltage. it also could have something to do with the fact that the 165s are way more popular in desktops than the 170. thats probably a big factor. they are both great cpus, tho.