Question PC shuts off upon power failure even with UPS

AlteredReality

Honorable
Jan 18, 2013
27
0
10,530
I got a new PSU (EVGA Supernova 650 P2) a year or two ago to be able to power a GTX 1080. However, as far as I can tell, ever since then whenever a transformer explodes in my neighborhood (which happens rather often), my PC shuts off, even though it is connected to a CyberPower 1000AVR UPS. The UPS itself stays on when this occurs. This didn’t seem to be a problem before the new power supply.

After some research, I found several posts saying that “active PFC”, a standard spec among many modern PSUs, interacts badly with UPSs that have “simulated sine wave output”. My UPS does indeed have a simulated sine wave output, and it appears logical (even though I can’t find the spec anywhere) that the EVGA power supply uses active PFC.

Does this seem to be the issue? If so, I don’t mind getting a new UPS with “pure/true sine wave output” if it means protecting my PC from sudden power failure. But, I don’t want to do all that if that’s not the issue.

Thanks!
 

AlteredReality

Honorable
Jan 18, 2013
27
0
10,530
there is a delay when UPS kicks in and another delay to match waveform, it should be in matter of few miliseconds (industry standart is 15ms)
your PSU doesnt seems to have enough juice to wait that long
Thanks for the reply. I didn’t know that.
And, after further research I found online that my old PSU (Antec EA-500) also had active PFC. So maybe it doesn’t have anything to do with that...

Is it possibly because my new PSU is 650W and the max that my UPS can take is 600W? Interesting thing is that my PC will shut off upon power failure even when idle, when it’s not drawing anywhere near 650W...

Edit: Though I do keep reading that active PFC really does need a sine wave UPS. But, then why did my old one work fine? Maybe the issue has to do with both, the difference in wattage and the active PFC/sine wave interaction?
 
Last edited:

AlteredReality

Honorable
Jan 18, 2013
27
0
10,530
Upon further research, I found that the issue may be that the UPS batteries are bad. I think I got this UPS in 2013 (6+ years ago), and the average battery lifespan for a UPS is 2-5 years.

I’ll post again if I find out anything more.