Hang on..........(1)pull the mobo from the case and place it on an anti-static bag. Plug in the power supply with the heat sink/fan and the CPU installed. If you get the mobo to power on then you can start from there(you will need a power switch pulled form an old case or you can just look for the power LED to come on).. I'll explain what to do next if nothing powers on.....swap in another power supply. If nothing....you have either a bad mobo or CPU. I would also pull the heat sink and CPU from the mobo once it is removed on the anti static bag and make sure you didn't bend any pins during the install. (2) If the board powers on (LED or CPU/fan if you have a scavanged power switch) replace the mobo in the case and see if the heat sink and or mobo LED lights come on. If they do and you get a bunch of CPU beeps your in realy good shape now. (3) Start adding components starting with mem and the video card and continue until post fails and you have the culprit. It sounds to me, just from your description, that the motherbooard is bad. Intel CPU's are very rarely DOA and that PSU is rarely bad as well. Pleae let us know what happens.
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