I have a prebuilt HP Pavilion 590-p0045t desktop. My product specs say it has a 310 W internal power supply and Energy efficiency: EPEAT® Bronze registered; ENERGY STAR® certified. Does that mean it has an Active PFC power supply? Is there any way to know without opening up my PC tower? Do I need to get a pure sine wave UPS or is a simulated sine wave UPS like the CyberPower CP800AVR ok?