I have a zeebronics 600va UPS for my desktop system. Recently I had changed the PSU to Corsair VS650. Since then the UPS is not able to hold to fluctuations and restarts randomly. The battery inside the UPS is a 12V 7Ah. Do I need to change the battery or the UPS to avoid restarting of the system when there is fluctuation? Will it do any good if I change the battery to 12V 12Ah or should I completely change the UPS to a new one?