hello guys.i really need help here. i just received this video card amd r7 240 4gb.and my pc is not getting signal when monitor is plugged in the slot.im not using hdmi cable.tried to disable the onboard videocard in bios,did not help.and later i noticed gpu is not turning on at all.its plugged in correctly (triple checked it).my Psu is 400w. what is the problem...i appareantly cant figure it out on my own