Computer is HP DX2000MT, intel processor running windows XP Pro
Have searched the web for solutions and tried several. Here is what we have done:
Replaced Power Supply, heatsink w/fan (parts directly from HP), Replaced CMOS battery, Ram and put in a working HD.
Removed video card (used built in), NIC card, CD drive. Tested all wiring and reseated all connections.
Checked capacitors---none discolored or bulged.
Tested motherboard by pulling ram---get long beeps.
Now when we start to add back parts---first HD, then RAM. Computer begins to turn off about 2 seconds after it comes on. Fan in Power Supply is all that is running.
Any idea where we go from here? Call it a day and order another machine?
Thanks for your help!

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