psu question

[alien42]

general question

how important is active pfc on a power supply?

 

[Operandi]

The only pratical benefit is extended run on time on UPS backups.

 

[JBDan]

It does absolutely NOTHING for performance on your pc. Might lower your electric bill by a couple of dollars. 🙂 Importance of active PFC is in Europe not the states.

 

[CheesePoofs]

Originally posted by: JBDan
Importance of active PFC is in Europe not the states.

Why is that? Is it because Europe uses different voltages in their power lines or because of stricter energy laws ... or something else?

 

[Operandi]

Originally posted by: CheesePoofs

Originally posted by: JBDan
Importance of active PFC is in Europe not the states.

Why is that? Is it because Europe uses different voltages in their power lines or because of stricter energy laws ... or something else?

Primarily because it's a requirement there. APFC is much cleaner conversion method, no PFC or PPFC sends a lot of noise/feedback into the electrical grid. On a massive scale (large cooperation?s) it's much expensive to use.

 

[imported_Intelfanboy]

hmm

 

[JBDan]

Originally posted by: CheesePoofs

Originally posted by: JBDan
Importance of active PFC is in Europe not the states.

Why is that? Is it because Europe uses different voltages in their power lines or because of stricter energy laws ... or something else?

Its their energy "laws" , but other factors could be present that I am not aware of.

 

[BonzaiDuck]

This is an intuitive speculation, but I would think that if you're using a UPS / battery-backup system, it would make no difference whatsoever.

But essentially, what people have said above is pretty much correct, judging from what I've heard. Tech Report spent a paragraph or two explaining this in a recent review of some eight PSUs side by side. There remark is that "there is 'active' PFC, there is 'passive' PFC, and there is no PFC whatever."

 

[Operandi]

Originally posted by: BonzaiDuck
This is an intuitive speculation, but I would think that if you're using a UPS / battery-backup system, it would make no difference whatsoever.

But essentially, what people have said above is pretty much correct, judging from what I've heard. Tech Report spent a paragraph or two explaining this in a recent review of some eight PSUs side by side. There remark is that "there is 'active' PFC, there is 'passive' PFC, and there is no PFC whatever."

It dose make a difference, why wouldn't it?, it's a much more efficient process

 

[Slaimus]

I have come to the conclusion that active PFC is useless for the average person here. Your PC uses very little power compared to everything else. If you want to make a difference in terms of grid noise, get APFC for your fridge or cooling/heating unit. It makes sense for a lab of 100 computers, but not a personal one. As for UPSs, unless you have one of those really expensive UPSs that outputs a true sin wave, having APFC will not help prolong the power draw.

 

[Zepper]

Active PFC makes your PC look more like a resistive load to the power grid. The Power Factor of a resistor is 1.0 so that's perfect. APFC is supposed to get your PC's PF to between 0.9 and 1.0. IOW, it will be a very friendly load. It can also save you a few bucks a year in electricity. Can become significant if you are in charge of the budget of a large PC farm.
. If you are a tree hugger, then you're a hypocrite (almost always the case anyway) if your PCs aren't equipped with them.

.bh.

 

[kreja]

I was under the impression that pfc helped make your load more stable, if your household current was unreliable (brownouts, fluctuations), and that you could use a smaller ups...?

river

 

[Ripken]

I have a question. I just bought - Fortron Blue Storm 500W ATX12V V2.0 Power Supply with 120mm Fan, P4 and AMD ready, Model "AX500-A" -RETAIL.

The PSU does not specify that it supports SLI mobo's, but does that matter? I am interested in the ASUS "A8N-SLI Deluxe" nForce4 SLI Chipset Motherboard For AMD Socket 939 CPU, and am not familiar with the new SLI boards yet. I have no idea if i need a PSU combatible for these boards, or if there are adapters I can get.... anyone????

 

[Zepper]

Kreja,
. Nope, PFC is mainly on the AC side of the PSU - the job is just to align the voltage and current curves. Power Factor is calculated as the Cosine of the offset between the curves in degrees. For stability just buy a better PSU with larger caps - that's where most of the stability comes from. Of course, PSUs with aPFC are usually the top models in a given mfr's line at any given output level, so they get the best caps too.
.bh.