Hey all, I am wanting to build a gpu mining rig with an old pc I'm going to pick up. It's more for a little project and maybe some profitability down the road...one issue,

I don't really know what video card, mother board, power box ect.. I would need. Help me out?!

As well, what would be a good coin to mine? I was thinking ethereum while it's on pow and it would be cool to download te block chain but what else is there to look in to? I'm going to be doing my research but welcome all and any advise!!