Chosen Solution
The PSU has a green light, but i press the power button and the pc does not turn on. I disconnected a cable from the motherboard that had 2 yellow and 2 black wires and all the fans started spinning, but the pc was not on… It is a 8104Y2B Lenovo IBM thinkcentre. I ordered a graphics card for this pc, so i want to get this pc fixed before it arrives next month (February). All help is greatly appreciated! Thank you in advance.
The 2 yellow and 2 black is the CPU power. That is signal to a short in the power leads on the psu or in the board. Has there been a power surge or a popping sound? I would try reseating the CPU. Make sure there is no dust in the socket. Is it a LGA or PGA CPU? . If that does nothing replace your powersupply. If it still fails to boot then you will have to replace your motherboard.
