Not to sound like a **** or anything, but you are working with a 500-1000US budget, claiming you will be starting a download server on a T3 line with your "bro"
Basically your an old me and a bunch of other guys on this forum, 14 years old, lots of warez, not alot of money but alot of mind.
If you can't even figure out what hardware to put in this "server" of yours, you won't have a clue on how to setup a T3 line.
With that beign said, I love my Asus mobos, go with an Asus if you can find one.