Build it yourself. It's easy, and you get allot more for your money!
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Newegg rocks! But a while ago here we tried building a base Mac Pro off of Newegg parts and couldn't get the price as cheap as what Apple sold the Mac Pro for. That didn't even include an OS or software. It could be different now, but building yourself isn't always cheaper, as the OEMs get crazy volume discounts on the parts. They especially get SWEET deals with Intel to stick with their chips over AMD.