Actually I have an Alienware m18x and I have the 560M but I want to put a dual 580M, I spoke to Dell as well as my local Alienware reseller they told me it can be done 100%. The problem is I dont live in America or Europe and the reseller is selling this for an outrageously high price they claim its customs duty but i doubt it. So I figured perhaps I can find 2 580Ms and then give it to the authorized service center here. They told me if i can find the GPUs then they would no problem replacing it, at a small fee (ofcourse haha)