Change Domain PW?

Have a network of 23 users on a windows 2008 r2 domain 1 server controls the dns, dhcp,AD

there is another server for a database program they use for inventory.

I want to change the domain user pw for both servers due to  security reason that have arisen.

I know how to change a pw on the domain my question is what do I check or make sure of that will effect the changing of this?

Or when I change it does that change then trickle down and all still works just fine.

Thanks so much for any and all advice in advance.