Rebuilt will not start up the first time

Why is this a rebuild? Start by removing all cables except the floppy cable. Then remove all added cards except the video if it is not on board. The mother board may need the P3 connector or the small, square connector in place. Some main boards need two power connectors, the long connector and a square connector to power up. Have a power conector to the floppy drive, plug in the keboard, monitor and mouse. Have the memory in correctly, power it up. Do you get any beeps or any thing on the screen?
If not you may have a bad power supply, there is a cheap tester you can buy to see if the power supply is bad. It is alot cheaper to do this then to replace the CPU or the mainboard. Did you use all the screws to put the mainboard in? Some are used for grounding.
Try reseating the CPU and check that the CPU fan is plugged in to a power plug. If you tried to start the computer with no memory and did not get any beeps then I would think the mainboard or CPU is bad.

The reason the fan tries to start and then stops
is the crowbar in the power supply is sensing a
shorted output. Double check that the stand-offs on the underside of the motherboard are insulated. You may have not noticed this when you disassembled the mother board from the case.
Try it with no cards installed, memory or plug-in
THe fan on the power supply should turn when the
faulta re removed. Then add the memory and then
the plug in cards. Keep an eye on the fan when
you add each card, this could tip you to the faulty device. Double check the voltages at the
motherboard. Then if all else fails, replace the
power supply.

Another thing to look out for on AMD M'Boards is the Video Card if it's not already On Board quite often if you chose the wrong one it will stop the unit from running at all.

The problem revolves around Chip Set's and the way that they Interact with each other and just to make things interesting the same Chip Set Video Card from a different maker will often work on that same M'Board.

I would first be looking at the Video Card if you have a Plug in one and try a different one, if you have On Board Video then all of the above apply.

Col

It sounds like your power supply is defective and since it is new, replaceable under warranty. Use a meter to check for power out put at the Connection on the mother board and make sure it is plugged in correctly, to determine this. If it was off warranty I would suggest opening it to see if it has blown its fuse. Some power supplys have easily changed fuses others require a bit of skill with a soldering iron; in either case make sure the fuse is properly seated or connected.

Make sure all the switches or jumpers are set properly. IF the MB has on board video and you are using a plug in video cardmake sure the on board video is disabled. Make sure the card is in the appropriate type of slot and it and all other cards are properly seated. Clean all connections with Q-tips and isopropyl alcohol.

I am assuming the reason for the rebuild was to upgrade your mother board. I hope you didn't overly flex the board during installation and perhaps brake a trace or cause a cold connectionat any socket. Make sure the simms or dims are properly installed and seated.

Make sure all wires and cables are installed correctly and that there are no instances of crossed polarity.

If it is a new mother board, hopefully you installed all the standoffs and did not over torque them.

Your starting point has to be the power supply and you must make sure it is puting out power. One other thing with power supplys, many are dual voltage, make sure yours is swithched to the correct voltage as the switch might have been inadvertently reset some time in disassembly and reassembly. I suspect the trouble is your power supply and if it is the one from the initial hardware setup you might have bumped it or thumped it sometime during your rebuild also if you cross polarized it during assembly, the fuse would have blown. Use your nose; if you can detect a burnt smell from the power supply, it's fried and you need a replacement.

[b]Dawg[/b] ]:)