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I'm looking at getting a UPS for my home computer. So far the APC BR700G looks very promising, except for one thing: one of the reviews on Newegg says that this UPS does not work with a power supply with Active PFC.

Pros: Unit looks great, built well, very heavy, was excited to use it.

Cons: Didn't research enough - many newer power supplies like my corsair 750w (and yes dells and other mainstreamers sell them too) that I bought last year have a feature called active pfc (power factor corrected). The signal for this backup battery doesn't fully support that feature and can cause issues.

You can find an article on APCs site if you search their user forums for PFC.

And the power supply in my computer is, in fact, an Active PFC PSU.

I've already found one answer on this site claiming that it's not an issue, that "most quality supplies these days have PFC and work just fine with a UPS." That disagrees with the review on Newegg. Can someone explain this discrepancy? Also, what is it exactly about a UPS that makes it incompatible with an Active PFC PSU? (if anything) Is there some way to tell based on the technical specifications, or do I just have to hunt for reviews online to avoid wasting my money?

While any input would be appreciated, I would prefer to get an answer from someone with actual experience with similar UPS's and Active PFC power supplies, who can tell me whether it works or not.

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1 Answer 1

There relly shouldn't be any problem with active PFC, because if it is done in a really good way they UPS shouldn't see the PFC, it'll just see the voltage and the current almost in phase with each other.

The problem with that UPS would rather be the low power rating it has, it will not be able to power a high powered computer.

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