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Topic

philip 40 months ago

Got a PM on reddit recently about listing PSU tiers and PSUs with 30C rated components.

I've seen comments that some power supplies only have capacitors rated for 30C. Stop. Please stop. It's like a bad rumor that's taken on legs and the story gets more outlandish the longer it goes on. Next thing you know we'll have people saying that if the room exceeds 30C your PSU will take out all the components in your build. Oh wait, that's already happened.

If we're going to talk about specs on a PSU, show proof and talk technical details. Cite reliable sources. If you're going to say it isn't designed for gaming builds, show proof. (Marketing blurbs saying a PSU is designed for price-conscious users does not prove it can't power a gaming build.) Real and reliable bench tests don't lie.

As for my background, I studied and competed in electronics servicing. Even won at the national level. I loved it - I studied college EE textbooks in high school, studied EE in college until switching to computer engineering (effectively a CS major with EE minor). Electrical engineering has always been my first technical love, and it's a domain I continue to try and grow in. I've built plenty of circuits from class A amplifiers to custom PC expansion cards to (non-switching) power supplies, etc. Designed and built plenty of other circuits, and fixed many more.

Plenty of people talk about capacitors like it's some linear component - like if the capacitance value is double it's twice as good. But it doesn't always work that way. The values are chosen and tuned, and what size they need to be, what voltage they need to be, and what tolerance rating they need to have depends on how it's used and what kind of circuit it's in. Sometimes you need narrow tolerance caps. Other times, having one that is rated for -20/+85% (like a lot of electrolytics) is perfectly fine and the circuit is designed to handle that variation and remain in spec. That's the EEs job. There is not just capacitance, but also have leakage currents, inherent resistance, temperature coefficients, etc. It's not as simple as brand X vs Y. But people without the background don't know this, and assume that cap X vs cap Y is so much better, or that cap Z is bad, etc.

So when it comes to claims about components, particularly power supplies and voltage regulation, my bar for what constitutes valid evaluation and feedback is considerably higher. My tolerance for bogus facts and erroneous claims is extremely low. If you see posts on review sites talking about capacitor "performance", consider it with a high degree of skepticism. No EE that I know of talks about caps in some absolute term of "performance". There's rated specs and adherence to that, but not some linear scale "performance".

Comments Sorted by:

pegotico 2 Builds 8 points 40 months ago

I've seen comments that some power supplies only have capacitors rated for 30C. Stop. Please stop.

example: I'm sure the corsair CX series would work fine even at 40C. But if you check under tech specs

http://www.corsair.com/en/cx750-80-plus-bronze-certified-power-supply-cn

Continuous output rated temperature (°C) 30°C

I guess corsair does this to justify a 100,000 hour MTBF. So in conclusion it won't last that long. The RMi which is an excellent unit has the same 100,000 hour MTBF but rated at 50C.

So when it comes to claims about components, particularly power supplies and voltage regulation, my bar for what constitutes valid evaluation and feedback is considerably higher.

it would be great if you are able to get the proper equipment and start making reviews. :) We need more reviewers like jonyguru that are not biased!! It just hurts me to see people that once said something and now say the contrary because of convenience (this is very misleading to many people).

And again thank you!! for your hard work making this a great site!!

philip staff submitter 10 Builds 6 points 40 months ago

example: I'm sure the corsair CX series would work fine even at 40C. But if you check under tech specs

Right right! I don't dispute that number at all. Part of why I posted the topic is that I've literally seen this progression on these forums:

  • Corsair publishes spec of 30C continuous output
  • Then the bad claims start... Another person reads that and posts that they only uses capacitors rated for 30C... (sigh)
  • Next person comes along and posts that if you go over 30C, that capacitor is going to blow and take out all your parts
  • Next person comes in and posts that all of that series are ticking time bombs
  • (edit, because I literally just saw this today) Next person says don't ever buy from said manufacturer.

And then on and on it goes, until it become a meme or groupthink. That's what I'd love to see die off. Lets evaluate units on their technical merits, not subjective tiers. I'm a big fan of JonnyGuru and how they review PSUs. Perhaps one day we'll start reviewing PSUs in a similar manner, who knows. :)

PureBlackFire 1 Build 7 points 40 months ago

That's what I'd love to see die off

it's like a weed with infinite regeneration.

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Xorex64 1 point 40 months ago

What would happen if you have a capacitor that is rated at 30C inside a psu that was operating at 45 degrees celcius? It wouldnt explode, what would it do in that situation?

personwhoknowshowtobuildstuff 1 Build 2 points 37 months ago

If you could even find a psu with such capacitors, if it had overtemp protection, it would shut off. Also people dont rate psu max temp by capacitor.

johngerges582 3 points 40 months ago

We need more reviewers like jonyguru that are not biased!

Unfortunately many people link Jonnyguru with Corsair and automatically make the assumption that he is biased towards Corsair, even though Jonny Guru himself doesn't even do reviews anymore. The site is unbiased. Period.

pegotico 2 Builds 3 points 40 months ago

i was not referring to the person but to the site. Oklahomawolf has being doing the reviews for a long time and yes the site is unbiased as i said before. Here is proof to that!

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story6&reid=416

johngerges582 2 points 40 months ago

i was not referring to the person but to the site.

I assumed you referring to either Tazz or OklahomaWolf.

Here is proof to that!

http://m.memegen.com/ug7f7i.jpg

pegotico 2 Builds 1 point 40 months ago

i can't give you evidence, lol as i won't be buying that PSU anytime soon.. :)

tiny_voices 4 Builds 0 points 40 months ago

Not really true. That site fails to mention if they were sent the unit or if they bought it for many of their PSU reviews. It is a common practice with all computer components.

This is why we get decent cx750 reviews (even though anyone who knows OklahomaWolf knows that the cx750 review is cleverly worded and he knows it is not good), and much worse reviews. HardOCP for example BOUGHT their CX750, not had it delivered from Corsair directly.

philip staff submitter 10 Builds 5 points 40 months ago

So let's evaluate on data, not on "clever words". Measurements properly done on representative samples don't lie, and then it doesn't matter what editorial content there is surrounding it. No "do you work for them?" conspiracies or whatnot.

tiny_voices 4 Builds 1 point 40 months ago

Sounds good to me.

m52nickerson 1 Build 3 points 40 months ago

OklahomaWolf's review and HardOCP reviews show the same results. No evidence of a better unit in one over the other. The difference is how they write their reviews on PSUs across the board. HardOCP will put the hard "Pass" or "Fail" on a unit and will be very critical of any unit that fails. JonnyGuru's site has always written reviews that don't call units bad, or even poor if they will not harm you components or burn your house down.

Godzlegend1 3 points 40 months ago

Heh... This was bound to happen. Good post.

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EdInk 11 Builds 1 point 40 months ago

HAHA!

tiny_voices 4 Builds 3 points 40 months ago

This is all REALLY great info and it is great for people to read, but I really hope it doesn't make people think that any PSU with the right wattage/amperage for their build will be fine.

I do agree with only using concrete evidence to back up claims. Like if you don;t recommend the CX750, post the HardOCP review of it. Simple. Too many people run around saying things with no evidence.

There are also a REALLY big number of people who disregard common sense. For example people will say that a 500w PSU with 20a on the 12v rail and a continuous rating of 380w(MAX of 500w) is fine for a middle of the road gaming PC because no one can post a review of the unit simply because it is so awful that no company has wasted time/money to review it. I have seen this many times here.

RyRy 2 Builds 1 point 40 months ago

Couldn't have been said any better. 'Bout time someone did haha. Iv'e used the CX series a couple times in personal rigs and never had an issue. Every manufacturing corp. has its flaws, but to stack all the "Bad/Crap" title on this particular series is just not logical. Thanks for sharing that tiny :>

welshdiesel 1 Build 2 points 40 months ago

so what you are saying is you want to start reviewing power supplies yes? :)

philip staff submitter 10 Builds 2 points 40 months ago

I'd love to. I know having the proper testing equipment is not cheap, but it's the time investment needed that is the constraining factor right now.

welshdiesel 1 Build 3 points 40 months ago

your the people we NEED in this industry now. people that KNOW, not the 100's that just read the marketing specs and are now "experts". just saying....

piemancoder 1 point 40 months ago

Thank you Philip for posting this. No more "cx sux, it's tier 42 & has bad capacitors!!1!!" That's pretty cool how you did electrical engineering! Also, which PSU review sites do you reccomend? I personally trust jonnyguru, are there any others that are good?

tiny_voices 4 Builds 1 point 40 months ago

People should still understand that some PSUs are not great for their situation. This article will help them do so. If anything this will help people to understand that some of those units (CX,TR2,etc.)really are not OK for their system.

526christian 1 point 39 months ago

I'm a bit late here, but TechPowerUp and HardOCP are both pretty in depth. HardOCP is really critical, so if something passes with a gold or silver rating you know it's a good power supply.

These aren't dedicated PSU review sites but they're still a couple of my favorite for looking at PSU reviews. Hardwaresecrets also reviews a lot of cheaper power supplies among the more expensive ones.

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johngerges582 1 point 40 months ago

If we're going to talk about specs on a PSU, show proof and talk technical details. Cite reliable sources.

Thank you!

Electrical engineering has always been my first technical love

That's cool. I actually plan to go into that field.

EdInk 11 Builds 1 point 40 months ago

It's exciting. I'm currently studying Mechatronic Engineering so I will be dealing with low voltage circuits. I might call on Phil someday for some advice.

johngerges582 1 point 40 months ago

And I'll call you.

If I do go into that field, I'll probably end up exploding something.

m52nickerson 1 Build 1 point 40 months ago

Thank You!

EdInk 11 Builds 1 point 40 months ago

Thanks for posting this Phil...I hope people see this and make better judgements when choosing a PSU and build within PSU constraints rather than hearsay.

I'll be bookmarking this link :P

ROG2000_PCs 0 points 37 months ago

Arguably, most people's PC rooms aren't going to be over 25*C unless they live on the equator. =I

unicykle 3 Builds 1 point 37 months ago

Lol You're welcome to come and visit :P https://s.yimg.com/ea/img/-/160204/2016_02_03t23_15_24.433z_640x360-1bb52pc.jpg
(that was this month)

ROG2000_PCs 1 point 37 months ago

Alright! I will =)

ROG2000_PCs 1 point 37 months ago

Dang...

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Xorex64 1 point 40 months ago

80 plus gold, fully modular, from evga.

Make sure to change the country settings to your country when you get to the linked page.

Xorex64 1 point 40 months ago

And here is the results for the johnnyguru review of the psu

http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story6&reid=440

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