hi.the last days my pc is doing a very weird ticking sound.it goes on and off so i could not check by openinig the case because it doesn not last long.the weird thing is that one time the sound continued after i closed the pc and it only stopped when i unplugged it.i'm thinking maevy it is the psu,xfx 550 core edition,but its new,i have it almost a month.any ideas??i know it is not the fans or the hard drive because that sound does not match the one that they make