Wifi and wired connections disconnect

I have two users, one using an Optiplex 5080 and the other a 7010.  Both are micro form factors.    The issue is that both are randomly disconnecting from the network.   They were originally on the wireless, but after the disconnects started I switched to wired.   However they still continue disconnecting.  It is only once or twice a day but has become a nuisance.    Anyone have similar issues?