My son built his own computer and used a Thermaltake T2 700W power supply. After 22 months the PC quit working-wouldn't turn on. I am a bit of a technician so I tried to troubleshoot the PS. The LED on the CPU motherboard lights up but I can meter no voltage on any other connectors. I went to Frys and bought what I thought was the same unit but the Atx12v connector on the motherboard is 4 pin. The new ps does not have 4 pin connectors. So now im confused when the specs say the ATX 12v connector is 4 pin. Why did it change?