For the last few days, my ups is making beepimg noise for prolonged periods when I am playing games. But the noise starts at different times. At times I play for hours without any problem. Is this due to some problem in the ups or simply due to voltage fluctuation?
Which brand/model of UPS do you have?
A beeping can mean one of several things, such as battery failure, overload, low/excessive voltage, internal fault, power fluctuations, etc. If this only happens while playing games, it’s quite possible that the UPS is overloaded, since the graphics card draws a lot of power. If you recently made an upgrade to your PC, such as adding a second or more powerful graphics card, this may also indicate an overload.
Check which LED lights up while it is beeping and look at the icon next to it. If you still have the user manual for it, it will have a diagram explaining the LEDs.
If your UPS is an APC brand, this page explains what the icons for its LEDs mean.
Generally-the battery has failed. This is particularly true of APC UPS units.
The load on the UPS will determine the run time it can provide and little else, since the UPS battery is supposed to take over ONLY when there is a failure of the 120 AC source. If you happened to have had a major power failure and/or a surge caused by lightning-that could be the cause of an internal failure. In the case of APC this usually means the unit will shut down and require factory repair.
Hope this points you in the right direction.