@skvderoesp
I'm honestly clueless as to what could be causing this then. Unless you have a REALLY specific hardware failure that only battlefront can bring out.
My MSI R9-270X 2G Card was running perfectly on my corsair VS450 power supply when I gave it a quick match in Battlefront at ultra+TAA 1600x900 earlier.
Allow me to get you a screenshot of my Crimson settings so you can copy them to your own. ( I will have to do this tomorrow GMT+2 as I have left this gaming box of mine at the office.)
Until then, I suggest, if your card has the dual-bios switch (as mine does), try turn off your pc, flip the switch on your GPU, then boot up and try to play on the secondary bios.
The only other thing I can think of right now is to check what happens in windows event viewer at the time your computer crashes.
EDIT:
I do so many of these forums for GPU help, I forget what I've asked you.
Could you please download FURMARK and run a GPU stress test (not a benchmark) and let it run for 10 or so minutes.
(fullscreen, 8x MSAA, whatever your native resolution is)
Could you then tell us what your maximum temperature was when running this?
Just realized this could be an overheat if it dies like this after 20 minutes of gaming.