Finally have a workaround. [URL]
I have a concern about installing Ubuntu on the X51. I'm not sure if it's the harddrive format or the X51 A02 BIOS version, but once I try to install linux via live USB stick it doesnt' work. And as for live CD I have the CD popping out of the disc issue. I've googled Alienware X51 + Ubuntu, but I don't find any information whatsoever. I might be one of the first in the community to bump into this, and I'm pretty sure more people as well use linux on there Alienware desktop. I bought it because of the tech specs and the portability size so I could have a portable desktop for my heavy 10-hours research computations. I hope you could give me some insight on the ubuntu linux install on the alienware X51. So far what I get is this: I get to the boot screen, but when I hit enter on "Install Ubuntu", I get a black screen and it stays there. So maybe the BIOS is detecting the USB stick but doesn't know how to run it?  Mecasickle
Linux Ubuntu on Alienware X51