Re Corsair HX620 review

[KTE]

http://www.nordichardware.com/Reviews/?skrivelse=504

Nicely done. The more different units different reviewers get to test for us the better it is to get an average feel of the product. :worship:

I've seen 3 bad and around 7 good reviews of the unit. A few questions:

1: The synthetic full load and minimum load test, how was that done :?:

Was that a computer used to put the load or something other, like resistors or a load tester?

2: Is there anything that made you feel the unit was faulty?
(thats what people are saying)

3: I didn't quite understand this from p4:

The greatest output from this PSU is at about 55-60% of the maximum load, which is about 340-370 W and we haven't come near those numbers.

Does that mean the best efficiency of the PSU was at 340-370W but you didn't test it to that amount of power? :?

Thanks for the help!

[Delph1]

I've forwarded your questions to Patrik, he knows the first three a bit better than I do.

The computer test (p5) is where we test it at ~60%

I realize it's not that obvious now.

//Andreas

[KTE]

I've forwarded your questions to Patrik, he knows the first three a bit better than I do.

The computer test (p5) is where we test it at ~60%

I realize it's not that obvious now.

//Andreas

Thanks Andy!

I realized that page 5 was a computer test, but I didn't know how teh "synthetic test" was done mainly.

[Delph1]

Patrik should appear sometime soon, he works odd hours

//Andreas

[Norrko]

Hello everybody!

To answer KTE's questions..

1. The minimum load test is made by just applying a resistive load to the 4 main rails. The load is a minimum requirement to make this PSU work, and it's done just to make it able for us to take voltage readings on all the rails.
In the full load test, we apply a purely resistive load onto each rail.
For example, we applied a resistive load on each single 12V rail worth almost 12 Amperes.

As the total maximum load is 600W, total maximum load for 3.3V and 5V is 170W, we have 430W (600-170) over to spread out over our 12V rails.
As we have three 12V rails that is 430/3= 143.333W per rail.
143 Watts divided by 12 Volts is 11.94 Amperes.

So, each rail were loaded with a resistive load of almost 12 Amperes, and that's how we made the synthetic full load test.

The computer test is just to test how the PSU behaves in a typical computer configuration, but we also applied a dummy load to reach the "golden peak", where the most efficient peak of this PSU are, which is around 340-370 Watts.

2. The unit where in no way faulty, the only negative thing we found were the rather high price tag and lack of information in the manual. But the PSU itself worked perfectly.
I didn't understand you really here, does people say that we thought the unit were faulty or is it a common opinion that this unit is faulty?.

3. There's a little typo there, the correct sentence is "the most efficient output from this...."
We actually made the computer test in that range as we applied a 150 Watts dummy load, just to reach that range where the PSU is most efficient.

Regards Norrko

[KTE]

So, each rail were loaded with a resistive load of almost 12 Amperes, and that's how we made the synthetic full load test.

Thank you

It would be very worthwhile for others if you would write a brief article that you link at the start of every PSU review covering how you test a PSU.

Believe me, many are confused. I had understood how the loads were calculated and gave you benefit of the doubt regardless, as you explained that well in the article and I'm not new to PSU testing. However, many looks for little faults to discredit other reviews and they are followed widely online. I wasn't aware how you managed to obtain the loads in the synthetic test, i.e. using which apparatus.

The computer test is just to test how the PSU behaves in a typical computer configuration, but we also applied a dummy load to reach the "golden peak", where the most efficient peak of this PSU are, which is around 340-370 Watts.

Ah, now I didn't know this one.

2. The unit where in no way faulty, the only negative thing we found were the rather high price tag and lack of information in the manual. But the PSU itself worked perfectly.
I didn't understand you really here, does people say that we thought the unit were faulty or is it a common opinion that this unit is faulty?.

Yes and no. :P

Online PSU "enthusiasts" are now quite insinuating. There are a few testers who follow a certain 'way' of testing, marking and reviewing a PSU and they only accept that or very similar ones as valid testing. They don't value others which can be seen if you visit their forums, although majorities do it differently to them.

Now those guys normally give it a score out of 10 in the end of the review. They drop the total score to 7/7.5 if the PSU drops 0.30V during testing on any +12V rail and consider it very poor "voltage regulation". They also don't recommend them PSUs at all and will make repeated comments on how to stay away from them or that there are many others better.
The unit you tested is very expensive in its range, has been giving buzzing issues with many people which can be seen on Corsair forum (thehouseofhelp.com) and it also dropped 0.64V max on one of the +12V rails in the synthetic test from the minimum to the maximum loads. Furthermore it dropped at least 0.6V on every +12V rail and around 0.42V on the +5V rail. This is usually considered very bad by other online reviewers who follow the marking criteria I outlined above.

This particular Corsair HX620 is loved by them, i.e. for instance by [H]. When they reviewed it, it did very well and since then, they have gone around everywhere touting is at the best there is in its class, faultless. So when they see a review that shows it not as good as their own review, they say "the PSU was faulty that's why", "don't pay attention to it" OR say "the testing method is wrong/iffy" -- unless you have expensive equipment like them.

When I saw your review on another few sites linked, I read the comments people were making and the moderator/admin were replying back in the same way as I stated above, i.e. making excuses. Because by their standards, the PSU did VERY VERY badly and would not be recommended. At this moment in time it is Number 1 on their list

That's why I asked if there was any chance it could be faulty. I don't see there was, because the ripple stayed perfect and everything else looked ok. Just that units differ like you mentioned. You either get a cherry picked one or you get a bad batch, and the end user will mostly never find out what he got until it causes damage or fails. But others who are followed online were saying that it was clearly a faulty unit, which to me seemed wrong and like they're making excuses due to brand favoritism.

For measuring voltages, you used a multimeter right?

3. There's a little typo there, the correct sentence is "the most efficient output from this...."
We actually made the computer test in that range as we applied a 150 Watts dummy load, just to reach that range where the PSU is most efficient.

Regards Norrko

That makes perfect sense. Thank you Patrik.