Power Supply

i recently took the battery from the motherboard and replaced it.
following that whenever i plug in the power supply cord, the computer
starts up automatically.  i'm figuring that it must be a change in
the BIOS to cause that since the BIOS was reset, i can't remember what
caused me to take the battery out but now that this problem exists, i
don't know what settings i should change in the Power Management,
because all looks fine to me which is obviously not the case

Any advice please?