"The IDE cable is upside down or off by a row or pin."
Sorry if this doesn't apply, but I don't much to work with so I resorted to my stack of envelopes for an answer.
When trying to turn on computer power supply will come on for a very brief spurt then shut off. this will do this every time now unable to get power to stay on. Have tried other old power supplyies I Have accumulated each one does the same. Any ideas?