OK, next question.

Is it an ATX motherboard or is it a motherboard that has a cable
from the ps2 port to the Motherboard?

If it is an atx motherboard were there special drivers that came
with it?  if not I would have to assume the mouse is bad... take
it back to (Came apart)

If it has a cable make sure the cable is installed correctly and
if so take the connector off and put it on a couple of times.  There
may be some corrosion on the pins which keep it from working correctly.

Larry

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