Why an expensive power supply?

[Shahmatt]

I see a lot of small cases from China with power boards and adapters. You can also buy mini power supplies from picoPSU (USA), HDPlex (Germany) etc.

If I build a non-GPU integrated graphics PC seems like many of these pump out enough watts and I can build a small PC. Even 120W is enough if no GPU.

So my question, why invest in a more expensive ATX power supply if these can do the job?

 

[Ark Law]

Because the expensive power supply has a warranty length almost long enough for you to make baby, come out baby, and see that baby finish PSLE

 

[Shahmatt]

You mean cheap power boards will die sooner?

 

[Ark Law]

I'm saying that people like peace of mind and warranty.

 

[hexanol]

a cheap power supply would most likely take out other components too when it fails.

 

[Shahmatt]

I'm saying that people like peace of mind and warranty.

Aside from warranty. Is there a sound technical basis? Does having a better PSU protect PC components? Can the mobo regulate power safely? Will a good mobo with plenty of capacitors protect the PC components from a misbehaving PSU?

 

[jtjt00]

TS, you know about 80+ rating for power supply?

 

[wwenze]

TS, you know about 80+ rating for power supply?

External power bricks follow the Efficiency Level system, which is enforced by EU and USA. It's 80Plus that nobody gives a shot about.

 

[wwenze]

I see a lot of small cases from China with power boards and adapters. You can also buy mini power supplies from picoPSU (USA), HDPlex (Germany) etc.

If I build a non-GPU integrated graphics PC seems like many of these pump out enough watts and I can build a small PC. Even 120W is enough if no GPU.

So my question, why invest in a more expensive ATX power supply if these can do the job?

Please compare the price and wattage of those power supplies vs ATX

ATX is still the cheapest source of power

But if you don't need the extra power, then you can spend $30 on the 120W power brick instead of a 300W ATX power supply. Buy the right thing for the right job, everything has their places in the market for a reason.

 

[riotpatriot]

Aside from warranty. Is there a sound technical basis? Does having a better PSU protect PC components? Can the mobo regulate power safely? Will a good mobo with plenty of capacitors protect the PC components from a misbehaving PSU?

you thinking of this sibo
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story5&reid=324

 

[Shahmatt]

Please compare the price and wattage of those power supplies vs ATX

ATX is still the cheapest source of power

But if you don't need the extra power, then you can spend $30 on the 120W power brick instead of a 300W ATX power supply. Buy the right thing for the right job, everything has their places in the market for a reason.

Thanks for your reply.

For my case I am trying to make my build small. If I go with a powerboard with laptop style AC-DC 19V adapter I can achieve a compact build. With ATX I cannot have a small build.

However many people look down on these powerboards as inferior compared to full sized ATX.

So I just want to know why. If there is a technical reason I will choose a larger casing to fit ATX size. But if technically there is no problem (e.g - mobo can regulate inferior supply) I might as well choose powerboard.

 

[Shahmatt]

you thinking of this sibo
http://www.jonnyguru.com/modules.php?name=NDReviews&op=Story5&reid=324

2012 article. Hasn't technology improved since then? E.g - we see solid caps on nearly all mobos nowadays.

 

[Shahmatt]

TS, you know about 80+ rating for power supply?

I have read that for lower loads (say less than 120W) the efficiency is hard to achieve. Even 80plus PSUs may not achieve that.

If you use a 400W 80plus Bronze with a PC running at 90W idle then I don't think you are running at 80% efficiency.

Also since the power draw is small maybe the cost savings of buying gold or platinum is negligible compared to how much extra you will spend on electricity.

 

[jtjt00]

Beside efficiency, Gold & above PSU generate far less heat in operation compared to those at lower rating.

 

[Rocket3]

2012 article. Hasn't technology improved since then? E.g - we see solid caps on nearly all mobos nowadays.

A motherboard with solid caps may not survive a PSU (or power brick / board) that blows.

Don't use a cheapo PSU/power brick/board. Because when that sh*tty cheapo PSU/power brick/board blows, it can ruin everything in your PC. And you will be cursing.

I have read that for lower loads (say less than 120W) the efficiency is hard to achieve. Even 80plus PSUs may not achieve that.

If you use a 400W 80plus Bronze with a PC running at 90W idle then I don't think you are running at 80% efficiency.

Also since the power draw is small maybe the cost savings of buying gold or platinum is negligible compared to how much extra you will spend on electricity.

At low power loads, 80plus PSU may not run at or over 80% efficiency, but should still be more effieicnt than cheapo PSUs.

 

[wwenze]

Just to share: My TV rig running on a China board + a 120W power brick.

Thanks for your reply.

For my case I am trying to make my build small. If I go with a powerboard with laptop style AC-DC 19V adapter I can achieve a compact build. With ATX I cannot have a small build.

However many people look down on these powerboards as inferior compared to full sized ATX.

So I just want to know why. If there is a technical reason I will choose a larger casing to fit ATX size. But if technically there is no problem (e.g - mobo can regulate inferior supply) I might as well choose powerboard.

It will work, no worries.

There are real differences, but there are also imaginary differences invented by the minds of the people on the internet. And trying to differentiate them takes too much effort.

 

[LLCSG12]

it all adds up over the long term..

today is 120W but the power supply gets less efficient over time while your electrical components eats more as they age..

so likely u need to replace the cheap low watrage one more often which adds up to same costs as 300W 80+ ATX over the same usage period..

 

[wwenze]

At low power loads, 80plus PSU may not run at or over 80% efficiency, but should still be more effieicnt than cheapo PSUs.

What if I told you, external power bricks sold today need to be >85% efficient

More reading:
https://www.digikey.sg/en/articles/...iciency-standards-for-external-power-supplies

 

[tmfwy]

I see a lot of small cases from China with power boards and adapters. You can also buy mini power supplies from picoPSU (USA), HDPlex (Germany) etc.

If I build a non-GPU integrated graphics PC seems like many of these pump out enough watts and I can build a small PC. Even 120W is enough if no GPU.

So my question, why invest in a more expensive ATX power supply if these can do the job?

To answer this question, one must not be tainted by the literature of those with vested interests.

Firstly, for non GPU systems, a PicoPSU will be mroe than sufficient to drive trhe system
Be it a 160w or higher, it is more than enough

As an example. I am using a 230W ( Yes, its 230W and i am not confusing it with 230V ) to power an I7-4790+ ssd + hdd + GTX1060 6gb and it has room to spare for ageing.

I've tried Cheapo PSUs from China, our very famour VIOS PSU that rarely receives complaints, EVGA ANDYSON Silverstone, Corsair FSP CoolerMaster Antec bla bla bla

Firstly, There is a chance for a PSU to knockout the other systems.
The key thing to look for is OVERLOAD PROTECTION SURGE PROTECTOR
The older flats have a tendency to knock out PCs due to wiring issues. Older as in even sengkang old. It is very difficult to determine this unless
a. you have proper equipment
b. You work with equipment sensitive to power.

Aside from OVERLOAD PROTECTION, one can also delve into
a. FAN NOISE
b. ACTIVE PFC
c. Power delivery -> delta curves


When one is going into small systems, it does not make sense using a high powere PSU because the high powered ones are not designed to handle small loads and as such, will be more inefficient.

TO be brutally honest
PSU is one of those components that i buy and throw.
IT DOES NOT MAKE SENSE TO ME TO PAY $300+ FOR A 7-12Y WTY PSU when by that time, aging would have come in, and then can kena shove "WEAR AND TEAR". Once PSU spoil, chuck in the bin and buy a new one. Safer approach to change PSU and HDD every 3 years.

In summary
Things you should look for
ACTIVE PFC, SURGE / OVERLOAD PROTECTION

But for tiny systems, a PicoPS makes total sense

Most PSUs in general are at least bronze efficient.
An old method that in general works is that if the PSu is heavy it ought to be good. I say in general coz there are exceptions..

 

[wwenze]

Careful with the +12V current rating on the "picoPSU" that plugs straight into the 24-pin... the real original one is only 7A, some later ones are 6A, the China one I got is 6A, others may have even less.

To get higher current, you need one with bigger transistors/cooling. Which means bigger PCB.

Active PFC is the job of the primary side, which would be the job of the power brick. All power bricks sold today would have APFC. Unless China, but even then many of them still do anyway.
Surge and overcurrent protection would also be the job of the brick. Again, unless China, the bricks should have it. Whether the picoPSU would have overcurrent for its own +12V/5V/3.3V outputs however... check whether it has an IC that provides this protection.

As for efficiency: Haswell G3220

Idle: About 11W from the wall. Nice. CPU is undervolted by 0.075V
Gaming: 47W, and most likely higher than that if I use Furmark
Normal H.264 video: Around 20W regardless of decoding method... the readings fluctuate too quick and the values too insignificant to care (It's just a few watts...)
Hi10P CPU decode: 35W to almost 40W spikes seen