SPCR

As you all know the great silentpcreview-psu reviews are done
at 120VAC, but those results differ quite a bit from 220V AC results
which I for one are more interested in, living in Europe.

Question:
1. Is there a possibility the silentpcreview might test at this voltage in the future?
2. Do you know of a serious site doing this today?

1: I'll let MikeC answer
2: Xbitlabs.com does their testing at 220. They don't do any acoustic measurements, but their electrical testing is among the best I've seen online.

Firstly, do you think the difference is really that significant?
I don't think it is. If anything PSUs are better in Europe because (AFAIK) the certifications are stricter. Also the 220V would result in higher efficiency PSUs (at least from what I've read of PSU flyers).

Secondly, is it important?
After all what you're looking for is a releative comparison. Won't the relative differences between PSUs be the same at 120V and 220V? Maybe they won't, maybe some PSUs perform better at 220V, but I suspect the differences will remain pretty much the same.

Rusty075 wrote:2: Xbitlabs.com does their testing at 220. They don't do any acoustic measurements, but their electrical testing is among the best I've seen online.

Wasn't there a SPCR regular who set up his own quiet PC related site in France? I think he did some reviews too.

Yes indeed: http://www.pcsilencieux.com/

But I don't think he does very many PSU reviews (only 6 to date)

[quote="DonP"]Firstly, do you think the difference is really that significant?
I don't think it is. If anything PSUs are better in Europe because (AFAIK) the certifications are stricter. Also the 220V would result in higher efficiency PSUs (at least from what I've read of PSU flyers).

Secondly, is it important?
After all what you're looking for is a releative comparison. Won't the relative differences between PSUs be the same at 120V and 220V? Maybe they won't, maybe some PSUs perform better at 220V, but I suspect the differences will remain pretty much the same.[/quote]

Firstly: Yes! I´ve seen reports on big differences (without giving an example), and in the quest for a silent pc that´s significant.
This might for example mean some cheaper psu´s are more silent for the money than the more expensive ones if the performance converge at 220V.
I don´t know, but maybe different manufactors optimize their PSUs for a certain voltage and if that is 120, 220 or something in the middle that would give different results.
We can´t know for sure until it has been tested!

Secondly, is it important?
I think so until a possible constant addition in efficiency has been confirmed between different brands and models. I´m not a believer in that constant so I definitely think it´s important.

Good point though :)
Maybe I also should mention we today have 230V AC in Sweden.

If it's a constant addition (say, of 5%), then I can't wait for SPCR to review their first 95% efficient PSU...


It's going to require a powerful step up transformer of 700VA or more (depending on what SPCR intend to review, of course). I can't say for the US, but I seem to remember they were about £80+ over here.

StarfishChris wrote:It's going to require a powerful step up transformer of 700VA or more (depending on what SPCR intend to review, of course). I can't say for the US, but I seem to remember they were about £80+ over here.

Huh? We have 230V circuits here in the US (presumably Canada too) in homes as well. They are used for things like furnace blowers, electric clothes dryers, stoves, ovens, table saws, lathes, etc... It would probably cost more than £80 though to have such a circuit installed by an electrician, however.

ilh wrote:Huh? We have 230V circuits here in the US (presumably Canada too) in homes as well. They are used for things like furnace blowers, electric clothes dryers, stoves, ovens, table saws, lathes, etc... It would probably cost more than £80 though to have such a circuit installed by an electrician, however.

Would they really charge that much for adding lines and an outlet? I thought most homes receive 230~240V with a center tap reference.

You learn something new every day! (we only have the higher voltage, as far as I know)

It takes five minutes to add a new 230v line. You essentially just combine both of the 115 volt legs. Running the wiring and outlet may be expensive though, depending on how complex.

slipknottin wrote:It takes five minutes to add a new 230v line. You essentially just combine both of the 115 volt legs. Running the wiring and outlet may be expensive though, depending on how complex.

In every place that I know about, only a licensed electrician is allowed to connect the lines in a panel box. Some places may also require getting permits and an inspection by the local authorities (the same for any type of home remodeling). The homeowner could probably run the wires to the box and save some money, if the work was inspected.

In the US, the standard is now 120/240.

The gist of the difference between 120 and 240 VAC operation is summed up in many PSU manufacturers' web sites: 2-3% higher efficiency at 240VAC operation. Or 2-3% lower efficiency at 120VAC operation.

It's possible that at 240VAC operation, some PSUs might actually run slightly quieter overall -- that's if the fan controller allows very small temp difference to be reflected in fan speed. On the other hand, a PSU w/such a fan controller probably would not get a good rating at SPCR because of the noise variability it introduces. (A fan that goes up/down often is usually much more annoying than a steady noise fan.)

I have to concede that a PSU with a good stepped-curve fan controller could run quieter to a higher power level if it was running more efficiently. The question is whether this difference makes any practical difference. The answer is maybe, but would this change PSU rankings at SPCR? Probably not. Would it bring a non-recommended PSU into the recommended ranks? Probably not.

Would it add more work. time, effort, and cost to PSU reviews? Yes.

At this point, I have to say there are better things for us to focus our energy and ettention on. In future, when we're bored and have nothing to do, we might consider doing some houe rewiring and PSU retesting. Don't hold your breath.

All I meant is it is probably $100 minimum for an electrician/plumber/etc to come to your house.

In our town, you can do your own electrical wiring in your own home if you get a permit ($15) and have it inspected by the town's electrical inspector (covered by the permit fee I believe). Other towns likely have different rules or prohibitions for such wiring by the owner.

The cost is not so much the electricals but the time & effort. A full set orf PSU tests takes the better part of a day right now. Running the tests at 240VAC means double this time. We just don't have that kind of time to put in, nor do we really want to. ALL of our testing / review processes are very time consuming and complex already.

m0002a wrote: In every place that I know about, only a licensed electrician is allowed to connect the lines in a panel box. Some places may also require getting permits and an inspection by the local authorities (the same for any type of home remodeling). The homeowner could probably run the wires to the box and save some money, if the work was inspected.

You can add a new breaker (115 or 230) in your box here whenever you want without needing to get it inspected or use a liscensed electrician.

Ive also had numerous installers of various appliances run their own 230 volt lines. They werent liscensed electricians, nor did they get it inspected...

Thats just nuts... Here in Finland you first have to be an educated electrician, and then work in the industry for like three years before you are allowed to touch anything over 50V(iirc) by yourself.

I have installed small 230V systems at school, and you really need to take a lot into consideration... Im still not shure i would trust myself to install something at home

Strange thing you have there with 115V and 230V for normal households. We have 230V for everything except larger machines wich is 400V three-phase.

Well, I have taken a few electrician courses, and Ive done quite a bit myself, ran my own sub panel, as well as setup a large GFCI system.

Of course, had I been consistently working with 230VAC I probably would have had someone else do it. I dont mind 115VAC as much. Ive been zapped a few times, but its no where near as dangerous as 230v is. I cant imagine working with 400v+. I tend to install GFCIs on every outlet and gfci breakers, so i figure if i screw something up. Just a little zap and no big deal (sure does hurt alot though). I do alot with aquariums (fish and coral farming) so its code to use GFCI near water anyways.

slipknottin wrote:You can add a new breaker (115 or 230) in your box here whenever you want without needing to get it inspected or use a liscensed electrician.

Ive also had numerous installers of various appliances run their own 230 volt lines. They werent liscensed electricians, nor did they get it inspected...

As I mentioned, it does depend on local regulations as to whether a licensed electrician is required to do those things. Some localities may not require licensing, but I think most do.

Also, there is a big difference between what someone "can" do, and what they are required to do if they follow all the permitting and licensing regulations.

m0002a wrote: Also, there is a big difference between what someone "can" do, and what they are required to do if they follow all the permitting and licensing regulations.

Well, I seriously doubt liscensed contractors would do electrical work if its not legal for them to do so.

I had a look at xbitlabs and they have done a great job this year!

The first I recognized was the OCZ modstream 520 reviewed here by Devon. I made a comparison only with the efficiency data and I guess I must have found an extreme example, here it is:

65 90 150 200 300 400 500 W load
77 78 77_ 78_ 76_ 75_ 73______ % efficiency from Devons data
81 83 88_ 88_ 88_ 88_ 89(450W)_ % efficiency from xbitlabs graph roughly estimated
4_ 5_ 11_ 10_ 12_ 13_ 16 <== additional efficiency

Both tested the American version of the PSU; the European version is equipped with PFC.
I guess this may not be representative but it makes you wonder... :?

simplex wrote:65 90 150 200 300 400 500 W load
77 78 77_ 78_ 76_ 75_ 73______ % efficiency from Devons data
81 83 88_ 88_ 88_ 88_ 89(450W)_ % efficiency from xbitlabs graph roughly estimated
4_ 5_ 11_ 10_ 12_ 13_ 16 <== additional efficiency

I have a lot of respect for xbitlabs' tech knowhow, but I don't buy those numbers. The fact that it is still rising at 450W seems really fishy to me; I've never seen that in any PSU, they start to drop as max rate power is approached. Also, if the efficiency was really that high don't you think OCZ's marketing folks would be doing a song and dance about it?

I realize that, now when I think about it.

Something with their test propably went wrong.
I read the article discussion and another efficiency was
also claimed to be different compared to a review made by Tomshardware.
Don´t know if that has something to do with this difference though.

[Added a comment/qestion to the xbitlabs discussion about this.]

If you know of a/some better example/s please share!

slipknottin wrote:Of course, had I been consistently working with 230VAC I probably would have had someone else do it. I dont mind 115VAC as much. Ive been zapped a few times, but its no where near as dangerous as 230v is. I cant imagine working with 400v+.

I've been zapped about six times with 240VAC.. (actually, it's 220VAC in the UK - they just didn;t tell anyone).
The point is, and correct me if I'm wrong anyone, that it's the current that kills - not voltage. So, a 115VAC zap is more dangerous than a 240VAC zap.
Or maybe not.. since the resistance of a human is fixed - therefore higher voltage, higher current. dunno.

Anyway - I have three phase 415V coming into my house I think

DonP wrote: The point is, and correct me if I'm wrong anyone, that it's the current that kills - not voltage. So, a 115VAC zap is more dangerous than a 240VAC zap.

BS

DonP wrote: Or maybe not.. since the resistance of a human is fixed - therefore higher voltage, higher current. dunno.

Correct.

Well, saying its the current that kills is only partially correct. It is both true that you can get hit by 10,000+ volts (static, car distributor, taser) and not be killed, and that you can be hit by 100 amps (car battery) and not be killed. The truth is that you need enough amperage to kill, I believe its something like .1 amp, and that you need enough voltage to penetrate the human body, which can depend on a variety of factors. (shoes, gloves, standing in a puddle, flooring, etc etc.)

Both 115 and 240 have far and away plenty of amperage to fry anyone. But 240 passes through the body far easier. Meaning it may find a better ground and be able to pull more amps through your body.

To add to what slipknottin said...

On the Voltage or current issue, I have taken multiple hits several times from motorcycle spark plugs/high tension systems (18KV + )... I'm still not dead.
People survive lightening strikes which are even higher, up in the realms of making normal insulators conduct. (Everything does given enough voltage.)

For an item with the same wattage there will be more current (Power = Volts x Current) at 110V than with 230V (which is what the U.K. should be now, to bring us into line with Europe, though down here in Cornwall I've yet to see it below 240V + ). However on building sites in this country the 110V supply is 'Centre Earthed' effectively halving any available voltage, thus rendering some 'Clutz' chomping through the wire safe.

Is the electricity supply in the States centre earthed? Or does the safety factor rely on 'Brown outs'?

And all houses in the U.K. have '1 Leg' of a 440V supply coming into their house, which is why it is possible for one third of your street to be without power whilst the other two thirds are oblivious.

Please don't ask me to explain how 1 Leg of 440V (Tri phase?...) becomes 220-240, it was 20+ years ago it was explained, it phased me out at the time and I've slept since then...


Perhaps you could expand on the reasons for your answers lm...


Love to All


Pete

peteamer wrote:However on building sites in this country the 110V supply is 'Centre Earthed' effectively halving any available voltage, thus rendering some 'Clutz' chomping through the wire safe.

Is the electricity supply in the States centre earthed? Or does the safety factor rely on 'Brown outs'?

Take what I'm about to say with a grain of salt, as I'm an electrical enginer, not an electrician. I believe that we have a Center Earthed system. I'm only familiar with electrical systems once it enters my house, so I have no idea what the power is like down the block.

Anyways, we have 3 wires entering our homes, 2 black wires and one white wire (I was going to say that the white one is sometimes uninsulated, but I just looked outside now and it appeared to be insulated. Likewise, I was going to say that the white one was thinner, but I can't tell from here). Between the 2 blacks is 240V and between either of the blacks and the white is 120V. Sometimes, if one of the blacks breaks loose, you'll only lose about half the power in your house. We refer to that as "Losing a phase."

To the original poster: see also reviews from www.dirkvader.de

As for kills, in humans, it's the combination of through current (not on skin, but through the heart) at 50-60Hz that kills. The frequency puts the human heart into a ventricular fibrillation and results in a cardiac arrest, unless a paramedic is on site to perform defibrillation through the use of an electric shock.

I've seen here on SPCR that there was a single reference to 240VAC test on a powersupply, and there was a difference, would be nice if SPCR could do a single test, taking the most efficent powersupply and see how much better it performs on higher voltage.