I'm having a issue with my studio 840 powering up. I jumped the green and black wires, both the fans and hard drive powered up. I also checked the voltages with a dvom and all the voltages were correct. i'm thinkning the m/b is ng but am still doubtful about the psu. i do have an old psu from a dimension 8100 psu, could i plug in that psu to see if it powers up my studio 840. if the 8100 psu powers up the studio than i would buy a new one for the 840.