the only time ive seen a situation like this is when multiple power consumers are using a single power line, in other words nakaTAP and some if not most of the power users are sharing the power bill or some of them are connected illegally to the legal connection, the only way to solve this is to have a separate power connection to the main line papunta sa mga poste, wala ka ba AVR? AVRs usually regulate the flow of power to ur pc incase of such said power fluctuation to prevent hardware damage, if wala ka AVR and nakadirect plug sa wall socket get an AVR