Today i recieved a AMD Athlon II X4 631 quad-core ive installed it and its showning that its only has 2 cores and 2 threads in task manager, cpu-z and piriform speccy. I have a generic 320w psu and i have to restart the pc several times before the monitor gets a signal for some reason im on win 8 btw, does anyone know why its only showing 2 cores is the cpu faulty i looked at the windows hardware panel and on the dropdown it shows 4 cpus which are all working??