Which is a better configuration for server?

I am building a server with an asus ATX server motherboard http://www.newegg.com/Product/ComboDealDetails.aspx?ItemList=Combo.176798 . What do you recommend for the chis and power supply? It will only have two or three drives in it and I prefer tower as I don't have a rack. I was looking at a Server Chis/PS (TruePower Trio 650W power supply) on newegg http://www.newegg.com/Product/Product.aspx?Item=N82E16811129027, but would like to go with something less expensive. I was thinking of getting a normal desktop case and PS such as this Roswill case http://www.newegg.com/Product/Product.aspx?Item=N82E16811147125 , and this BFG Tech PS http://www.newegg.com/Product/Product.aspx?Item=N82E16817702010 . I wasn't sure it was necessary to have a server chis or if everything should fit and work right with the cheaper stuff (is a server atx standard the same as the PC atx standard?) Do you think the server chis is a better buy for what you get? Thanks for all advice.