3 months ago my PSU gave up on life... so I had to claim an exchange of PSU.. now that I have my PSU (replaced with new - same one) back when I plug in my R6870 hawk GPU my pc wont start.. it wont even get to boot it just lights up and does nothing... no *beep* or anything. When I switched my gpu to low end one (x550 ati old trash). It has no problem turning on? Could my r6870 hawk be faulty? pls help