Educating users about power management will make them more comfortable with the technology. The monitor goes to sleep, then wakes up a few minutes later. This can be caused by some screensavers. If that is the case, the screensaver can usually be reconfigured to not do this. Avoid screensavers or screensaver options that require hard disk access, and make sure that the screensaver delay time is less than the first monitor power management delay time.
Some networks can cause a machine to reawaken after a short period of power management.
See if the machine power manages correctly when not connected to the network, and if so, if the server or network card can be reconfigured. This occurs if the PC goes into the doze mode, slowing the processor clock, while the computation is in process. If such calculations are rare, then either doze or power management in general can be disabled while it is in process. If the computer is routinely used in this way, disable doze only so that the rest of power management will occur. That machine might not be capable of power management.