IS7-V2 no post

Just put together a sysem. All parts from newegg.
IS7-V2, 1GB crucial 3200 ram, retail P4 2.26 533 FSB northwood core.

Put system together, powered on. Got green led on mb. Pushed ATX power
switch and red LED, fans came on for about 1 sec and then stopped. Could
repeat. No smoke, no smell. Reset CMOS, removed all cards and peripheral
connectors - same thing happened. Reseated CPU and memory same, removed
memory same. removed board from case and using different PS on table same
problem. I am at a loss. Doubt it is the PS so I am left with MB problem or
CPU problem. I do not have another 478 MB or CPU to further diagnoses. Any
suggestions from the Group?

Thanks
Howard