^ This usually means your PSU (Power Supply Unit/SMPS) is being pushed to its limit. Please mention the voltage of the line on which it is changing. As long as the increased voltage is within +5% of the default voltage it should not be a cause for concern . You can increase the "threshold" value of PC Probe to avoid notifying you about this.
If it is above 5% , its time to get a GOOD PSU.
Your UPS has absolutely nothing to do with it.