What kind of plastic is the Dell XPS 17 notebook cover?

I bought a Dell XPS 17 gaming notebook and it's not the light changeable one. It's been out for more than a few months and I customized the cover to the plastic one with Design Studio. I decided to do that instead of aluminum, so I can spray paint it. But the thing is, what kind of plastic is it? I want to know, so I can choose the right spray paint, without messing it up.What kind of plastic is the Dell XPS 17 notebook cover?It's either:
A. Plastic. Most likely ABS.
B. Powder coated magnesium alloy.

I don't think the new XPS's use magnesium alloy so it's probably the former. The old ones did though.

EDIT: Looks like magnesium alloy judging by the plastic band on top of the lid. If the lid has a plastic band running along the top edge, it usually points to a metal lid. (the wireless antennae are placed there if the lid is metal, since placing them in the metal lid would lead to really poor reception). Laptops with plastic lids don't have that band.