Where is the Advanced power armor?

Not entirely sure if this is right, but I've heard if you have Arcade as a follower, he eventually gives you a quest to go to some abandoned Enclave ruins. I'd assume the stuff is in there or somehow involved in that questline.

Outside of Arcade's Quest (and it's a doozy) the only other location I'm aware of where you can find Enclave Armor is in Silver Peak Mine (Located in the mountains Northwest of New Vegas proper up a loooong road). Mind you there's about a dozen or so Cazadors in there and all you get is a damaged helmet, but if you -really- want a piece of it, that's the easiest way I know of.