Normally the Freq regulation for 100 MHz Bus is about 1%, so a 3% deviation is on the High side.
.. Will 103 be a problem, In the majority of cases NO, normally most systems can tolerate a 10% deviation.
.. Some manuf do this to provide a small boost.
.. I would prefer a "solid" 103 over one that is verying 3% as that indicates poor regulation.
BOTTOM line - If not seeing Instability in system, don't sweat it. NOW if you see that variation keeps growing then it's time to ditch the MB.