Power supplies can do strange things if you use them [near] at their limits. And yes, they can cause surprises, random hardware failures without visible reason.

Hya,

Replaced motherboard, HD and memory.
PSU spec 170W.
ASRock J4105-ITX, 2TB disk and 8Gig memory.

I will update.

cheers

170W sounds weak to me. There's rakes of different supplies and current requirements. You can go overloaded somewhere and oversupplied elsewhere. Buy a 250W power supply.

you might want to check this: https://outervision.com/power-supply-calculator
or this: https://images10.newegg.com/BizIntel...alc/index.html
or something similar

Hya,

Thanks for reply.

Yes, I agree. These sites say 250-300W.
Two points I do not understand;
First point is that another my penguin ASRock deskmini 110 works with 120W power supply, (Core i3 6th gen, 4G DDR4 memory, one disk and one SSD). Aopen ones has even less than 100W power adapter.
Second point is that why penguin stay healthy for more than year and go wrong, if PSU is to blame. I guess it would be unstable from the beginning.

So far, no trouble, since my post #17.

cheers

Hi,

Most system are sized with the typical power for the total needs with a margin to allow changes due to load changes. Users must take into account the total power available so when one adds to the system the power needs are there without exceeding the available power for the PSU. The PSU is a electronic device and failure can be due too over heating, power surge or physical means. Individual components can fail thus causing the PSU to loose control to provide the current requirements. Dust can be harmful to a PSU by collecting within PSU not allowing the components to cool properly because the air exchange is poor because of flow through the case vents or fan.

As to your PSU requirements and size for the information given, each system is sized to allow the PSU to meet the needs required for each system. You did not give us all the peripheral equipment within each system so we cannot really tell you power needs for each. It's like comparing apples and oranges, each has it's own taste.

My guess is that your GPU in each is minimal and provides a doable graphics output to suit each system. I have worked on mini-desktops with 100W PSU but mostly textual/nominal graphics along with acceptable computational needs.

Hope this helps.
Have fun & enjoy!

This wattage is misleading. This wattage may be made up of
+5V@20A = 100W
+3.3V@10A = 33W
etc. etc. There's also +/- 12V and -5V, and possibly some ultra-low voltage output for today's chips. Now most, if not all of these are made with the one transformer. That design listens to none 'mission critical' supply rail usually and hopes the others will be okay. But a pc has 2 'mission critical' rails, the +5 & +3.3V. There's no standards that I am aware of, so supplies may provide what current ratings they choose.
The negative rails may go purposely high and have voltage regulators. This is Not practical with high current rails (+5V & +3.3. Light load will mean the voltage goes high, low load means it's usually low. +12v is usually fairly tolerant.

So most rails are there or thereabouts most of the time. But usage of any box is not predictable for the manufacturer. The 3.3v rail is hugely important now, powering the motherboard. Things may work well at 3.1V and 3.5V. They may not. Supplies may drop out on overloads, or they may just go low. It depends on where the strain falls and the individual design

Getting a high power supply at least cuts out overloads. A lower supply MAY work, but is a one off case - this supply powering this motherboard and those peripherals. Conventional wisdom is to buy big.

Hi,

Older PSU designs would use iron core based step down transformers that were expensive and bulky. Iron core design units had poor Power factor(PF) and load requirements that did waste energy. Each rail required separate circuit controls for each winding of the transformer.

Most modern PSU are ferrite core based torroid transformer instead of a iron core step down type which can be costly and bulky. Efficiency for a switched mode supply is the ability to provide required power rails with minimal lose thus better Power Factor(PF). Modern designs are switching power supplies to produce the required voltage and current needs for each rail specification.

PSU is fair representation for modern switch mode units that are widely used today in home and industrial supplies. Newer CPU designs utilize the +3.3 VDC rail instead of the +5 VDC. But the systems still require a +5 VDC along with a +12 VDC rail which supplies for the motor needs of the system. -12 VDC requirements are minimal today since serial communication via RS-232 are rarely used.

Power rating is not fully understood by most; Hope this helps.
Have fun & enjoy!

Yes, typical supply efficiency would be 50% or less for low frequency iron cored mains transformer based supplies, and 70% up for ferrite high frequency switched power units. Such supplies are usually 80-90% efficient?

Hya,

Thanks for posts.

Regarding to GPU, my J4105-ITX and ASRock deskmini 110 are on board (integrated) ones. The latter operates as a headless node for slrum cluster.

Yes, I have never thought of dust. Whenever I open the chassis, dusts are blown off.

5V 3.3V imbalance (5V heavy or 3.3V heavy) could be a problem. (Still it does not explain healthy period.)

How old is "old" (iron core)? How modern is "modern" ferrite core? When did they switch?

So far, my penguin is healthy.

cheers

The switch is because has huge losses at high frequency, which switched more supplies need. Pcs always had switched supplies

Healthy periods often relate to how much the PS weighs. A 300W rated PS that weighs half what another 300W rated PS weighs likely can be expected to last little beyond its warranty period, if that long, whereas the heavier one likely will last as long or longer than RAM, CPU and motherboard. If a power supply is included at no extra cost with a $29US case, it's likely super lightweight garbage good for use at most a few hours per week and beyond that little more than causing premature motherboard, HD or CPU failure - if it lasts long enough.

I've been building PCs for going on 3 decades, but only as tools, not toys for playing games, and with GPUs that work reliably without active cooling or a dedicated power connector. The highest rated PS I've ever bought is 500W, only once, with most rated between 300W & 450W. For most PCs I've built, 500W is at least double what the components require. My 3 newest Dells came with 235W rated PSes. Intel Mac Minis commonly ship with PSes in the 80W to 110W range. Overbuying PS rating is like equipping a 2500 lb convertible with a 7 litre V12 - inefficient loaded to a modest fraction of capability.

In sum, add up what the components require, then shop accordingly, taking potential expansion, product weight and brand reputation into serious consideration. If you can, conserve the environment by buying an 80 Plus or better rated model. And if you want it to last, either keep it clean, or clean it regularly.

Hya,

Thanks for your post.

Yes, I do understand what you mean.
However,
My first penguin - healthy for a good while, then gone wrong. (replaced motherboard, memory and disk)
My second penguin healthy for a good while then went wrong.

How to explain healthy period for the second penguin, if PSU is to blame.
Then my third penguin, (new motherboard,... same PSU) is so far healthy.

How do I know whether my PSU is modern ferrite one or not?

cheers

your PSU must be oversized - at least a bit. If not, some parts may be continuously [nearly] overloaded, which may kill the hardware much faster.

PS instability that violates specifications only randomly or at demand peaks or at elevated temperatures.

What is this PS brand and model? When was it manufactured? How much does it weigh, both complete with cables, and by itself?

Take the cover off this PS, and inventory the electrolytic capacitor brand names to provide here. Premium brands are Panasonic, Rubycon, (United) Chemicon (UCC) & Nichicon. second tier and cheap stuff are too numerous to list. Goto badcaps.net for help identifying product branding and obvious signs of cap failure. e.g. Panasonic caps traditionally do not have the string Panasonic on them anywhere, only an encircled "M" for Matsushita, Panasonic's parent company.