Why do people not use Xeon processors in gaming builds? Like this Xeon instead of an I5? It seems like if the Xeon's were built for servers they would be great for gaming.

well people do, but a few things

  1. xeons don't OC
  2. 1150 xeons aren't physically compitble with desktop boards
  3. desktop versions Usually have combo deals on newegg

but yeah for people who don't OC and looking for very low budget rendering builds I recommmend a ivy xeon i7 thats the price of an i5

Well, older Xeons can be OCed, on socket 1366 and earlier.