I have been attempting to replace the power supply in a Compaq Presario 5330US (Compaq P/N: 470019-713). It is a Pentium 4, 1.7 GHz with 512 RAM. The motherboard is Compaq: KSR1983077 Spider-S The power supply is a 235W (250W on plate), p/n 243890-001 It is not a standard ATX power supply, or at least the connector to the motherboard is not pinned to the ATX standard. It has a 24-pin connector vs. the 20-pin ATX (and it's not the latest 2.0 version). I tried a standard Antec PS and the unit failed to turn on, and the motherboard LED indicating power present does not light. AND the wires from the PS do not use the ATX color coding. Compaq does not offer a higher wattage PS. What are my options? - I would like to just splice my new power supply to the existing connector, but I do not have the pin-out to properly match up. Does anyone have a source for this info, and don't say HP/Compaq support.... Been there, done that... again, and again, and again...... - I want to upgrade the PS to accommodate a new video card (the card suggests a minimum 300W), should I just try it/chance it with my existing PS? ANY and ALL help is appreciated.