I have been shopping for a laptop that will be primarily be used for Programming (Low level stuff in DOS Box or Virtual Machines), and school stuff. I was looking at the $1000 price point and hoping for expand ability. I found the Dell Inspiron 15 7000 Gaming and was curious what you guys thought. I was planning on adding at least 8 more GB of ram or more and maybe an SSD depending on how slow the hard drive.
Here is a conversion one person did on an original Xbox.
http://www.instructables.com/id/Xbox-Original-Desktop-PC/
Also, did you mean you have a mini itx board?
I always go on pcpartpicker and see what I can get on sale. I don't recommend factory Oced because you normally have to spend $30+ for what you can normally do by yourself or go for the next tier like from 1070 to 1080. Right now Gigabyte seems to have some good deals on 1080's and I have used my 970 G1 Gaming from gigabyte since it was released with no issues.
Plug the monitor to the onboard video port, Boot into the Bios of the computer, and change the primary adapter from Onboard Video to PCI-E, then switch the monitor back to the 750 TI and it should work.