Power cuts, UPS & what needs to be protected

Hi,

I currently run the main computer with the Sage accounts on, accessed by two client pc's via a network.

The main PC is connected to a UPS, to maintain power when we get a power cut.

Is this sufficient to prevent data corruption within the Sage program if the power suddenly drops off of one of the client pc's, or of course the network, which has mains powered switches?

Or should I have a ups powering the network switch & other client pc. The other client is a laptop, thus can run on it's own battery if the power fails

regards

Steve