Recheck your connections.
Reduce the number of components(unplug drives) till you power up.
Check your power switch connector to the motherboard. Make sure you are on the correct pins.
Check for any errant motherboard mounting studs that may be shorting out the board.
I switched PC case and believe all to be connected correctly but there is no power. A DVD drive and USB card were not transferred from old case. Should I start over? Thanks.
ASUS k7m mobo, 800mhz

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