Question about keeping UPS on

[Hafi]

1. Unless your location have constant power failure, there is no real need for UPS for homes in SG.

2. Constantly keeping the battery at full charge, you will know that it will not hold the charge for long. So preventive maintenance of the battery comes into play.

3. The beeping sound of the UPS is quite irritating. If some family member accidentally off the switch while you are not at home and your UPS and PC are running, it will beep non-stop until your UPS battery flat or turn it back on. Your aggrieve family member will sure question you when you return home.

4. Lastly save electricity, save money and save yourself the trouble. UPS at home is not necessary.

1. if your location have constant power failures, you need to get your DB and MCBs checked. UPS are used to prevent un-usual occurrences that nobody can expect... its just like buying insurance if your hardwares or data are important/precious to you. Sometime its out of your control if any of your family member uses a defective appliance and trip the circuit breaker and shut off the entire house power supply. Even bangalas repairing/shifting lampposts/construction work outside/away your residential property can also trip up to the sub station where it shutdown power supply to the nearby flats as a safety precaution.

2. typically a good UPS is designed to work for certain numbers of hours during its lifetime under a controlled power load and once you deviate out of that, your battery life will wear off degrade faster. UPS batteries are consumables and are meant to be changed periodically once shelf live or charging capacity is reached.

3. The irritating beep is to warn/alert you in event of power cutoff/switchover so you can take action to restore power if you are around, if not there always the autoshutdown function where the UPS will safety shutdown your NAS/PC during a power failure without anone intervention. To prevent accidentally switch off the UPS button, you'll have to locate the UPS to a place where its not easily accessible or at least for anyone to touch it.

4. You talked like an UPS is some kind of an irritating and undesirable piece of hardware equipment without understanding it actual purpose and usage but I don't blame you for that since not everyone is well educated and informed in these. To be honest in the past I used to have the same mentality as you until I encountered frequent lighting storms the past few years around my area which abruptly causes power shutdowns (DB protection) which pushes me to incorporate UPS protection for every piece of my electronic equipment.

You don't give it a damn until you need or be bothered by it.

 

[westom]

Turning off and on your computers more than once a day, you are going to use in fact more power than leaving the computer on the entire day and leaving it at idle. ...

UPS above all else, will make your computer last a long time. In a way, it is like a water filter, always making sure your power levels are stable. Even with Singapore's stable powergrid, there are a lot of spikes and dips in power, which is not very good for your power supply and motherboard circuitry always having to compensate and regulate such irregular voltage.

Myths promoted only by hearsay and wild speculation. Even that 220-240 volt number does not say what is only speculation.

Turning a computer off means that computer is no longer consuming tens of watts. When it starts up, it consumes same tens of watts - just a little more.
Turning it off when done, even for five minutes, massively decreases power consumption.

That fluorescent light myth was also generated by wild speculation. By ignoring numbers. Turning it off for 15 seconds means less power consumed than power needed to restart a fluorescent bulb. Best is to power off when done.

UPS does nothing to filter power. Dirtiest power can come from a UPS in battery backup. Power is only cleanest when a UPS connects a computer directly to AC mains.

Power from a UPS is often so 'dirty' as to be a threat to strip protectors and motorized appliance. Since electronics are required to be more robust, that same 'dirty' UPS electricity is perfectly good for all electronics. Contrary to popular myths, wild speculation, and other hearsay - that make claims by ignoring spec numbers.

Voltage can vary so much that an incandescent bulb dims to 50% intensity or doubles intensity. Voltage variations that large (for electronics with a 220-240 volt label) are ideal. Voltages must vary that much and internal DC voltages do not vary by even 0.2 volts. Voltage variations cause no harm to electronics. Same voltage variations are potentially harmful to less robust central air, refrigerator, washing machine, and dishwasher.

Even more robust are portable electronics. Perfectly good voltages include 85 and 265 volts. According to that urban myth, using portable electronics in other nations is also destructive.

AVR, already inside all electronics, is that robust. So robust as to even make 'dirty' electricity from a UPS irrelevant. Subjective reasoning (claims made without citing any numbers) is always best ignored.

 

[uncle_josh]

LOL, You talk like every time bangalas repair/shifing lamppost there will be power supply kena cut off the entire household.

1. if your location have constant power failures, you need to get your DB and MCBs checked. UPS are used to prevent un-usual occurrences that nobody can expect... its just like buying insurance if your hardwares or data are important/precious to you. Sometime its out of your control if any of your family member uses a defective appliance and trip the circuit breaker and shut off the entire house power supply. Even bangalas repairing/shifting lampposts/construction work outside/away your residential property can also trip up to the sub station where it shutdown power supply to the nearby flats as a safety precaution.

Good that you reinforce this point
I bring up this to the attention to TS, so that he will be aware to keep a maintenance schedule !!!

2. typically a good UPS is designed to work for certain numbers of hours during its lifetime under a controlled power load and once you deviate out of that, your battery life will wear off degrade faster. UPS batteries are consumables and are meant to be changed periodically once shelf live or charging capacity is reached.

Unfortunately, unless you pre-plan and have a room specially for your PC else this kind of thing is hard to avoid. Also if you have senior folks around the house hold who are not tech savy, they will go around to turn off all electrical appliances.

3. The irritating beep is to warn/alert you in event of power cutoff/switchover so you can take action to restore power if you are around, if not there always the autoshutdown function where the UPS will safety shutdown your NAS/PC during a power failure without anYone intervention. To prevent accidentally switch off the UPS button, you'll have to locate the UPS to a place where its not easily accessible or at least for anyone to touch it.

Huh ???? Isn't all these consideration should be taken into account when you implementing a UPS in a household ? There are people who are even more sensitive even to the spinning of the fan of the CPU.

If you house electrical frequent abrupt power interruption due to lightning, shouldn't you be feedback to HDB & Town Council ? Yes, in this situation, a UPS comes in handy as a temporary solution.

4. You talked like an UPS is some kind of an irritating and undesirable piece of hardware equipment without understanding it actual purpose and usage but I don't blame you for that since not everyone is well educated and informed in these. To be honest in the past I used to have the same mentality as you until I encountered frequent lighting storms the past few years around my area which abruptly causes power shutdowns (DB protection) which pushes me to incorporate UPS protection for every piece of my electronic equipment.

You don't give it a damn until you need or be bothered by it.

 

[BlackLab]

Thanks for the input guys.

Ya I intend to have a proper maintenance schedule for it. Guess the battery usually needs replacing every 2 years or so?

I'm actually looking to get a UPS because the power has gone out in my home a few times before.
Very rare (think only 3 times since beginning of last year), but the first was when I turned on the oven, the second was during a heavy thunderstorm, so I thought those were situations that I couldn't really help, and just had to be sure to save my work.

But the last time, the power failed out of nowhere. No switches were flipped, nothing. Circuit breaker just tripped and I lost a bit of work, so now very wary of this.

 

[keenklee]

Thanks for the input guys.

Ya I intend to have a proper maintenance schedule for it. Guess the battery usually needs replacing every 2 years or so?

I'm actually looking to get a UPS because the power has gone out in my home a few times before.
Very rare (think only 3 times since beginning of last year), but the first was when I turned on the oven, the second was during a heavy thunderstorm, so I thought those were situations that I couldn't really help, and just had to be sure to save my work.

But the last time, the power failed out of nowhere. No switches were flipped, nothing. Circuit breaker just tripped and I lost a bit of work, so now very wary of this.

That's why notebook is marvelous device.

 

[Hafi]

Thanks for the input guys.

Ya I intend to have a proper maintenance schedule for it. Guess the battery usually needs replacing every 2 years or so?

I'm actually looking to get a UPS because the power has gone out in my home a few times before.
Very rare (think only 3 times since beginning of last year), but the first was when I turned on the oven, the second was during a heavy thunderstorm, so I thought those were situations that I couldn't really help, and just had to be sure to save my work.

But the last time, the power failed out of nowhere. No switches were flipped, nothing. Circuit breaker just tripped and I lost a bit of work, so now very wary of this.

its a no-brainer go for it but do remember to buy a model that have enough juice to support your desktop and peripherals, I would suggest a minimum of 1100VA one so you can connect your router, ONT and other sensitive equipments like NAS you want to protect, not just your desktop (if they are all located on the same area).

Also do note that some APC models battery cannot be replaced easily, for those you'll have to dispose and replace the entire UPS unit but they are usually low cost models below $200. The battery in the UPS usually can last more than 2 years if there no abrupt charging and discharging frequently and the unit is not overloaded with power hunger devices connected, the UPS unit will alert you when its time to replace the battery giving you ample time to make arrangement to switch it off, move to another non-UPS power outlet while you replace the battery/unit.

 

[westom]

No computer is consuming anywhere near 1000 watts. Otherwise it is so hot as to also toast four slices of bread.

Computers rarely consume even 350 watts. Often only 100 to 200 watts most of the time. However, since so many computer assemblers do not know how electricity works, we tell them to buy a 700 watt PSU for a computer that rarely consumes 350. Then help lines are not clogged teaching how electricity works.

A 500 watt UPS is often more than sufficient for a computer and its peripherals. So that a UPS can provide sufficient power three years later as its battery degrades. And for other electrical reasons.

If in doubt, purchase an inexpensive device that informed consumers use. A Kill-A-Watt will not only confirm these answers. It also teaches various parameters that define electricity and how all appliances really work.

 

[keenklee]

Computers rarely consume even 350 watts. Often only 100 to 200 watts most of the time. However, since so many computer assemblers do not know how electricity works, we tell them to buy a 700 watt PSU for a computer that rarely consumes 350. Then help lines are not clogged teaching how electricity works.

You are saying a 350W power supply is 100% efficient?

 

[westom]

You are saying a 350W power supply is 100% efficient?

Nobody said anything about efficiency. Power supplies were once only 40% or 50% efficient. Today's must exceed 80% or violate national standards. None of that says why we tell a computer assembler to buy a 700 watt PSU for a system that rarely consumes 350 watts.

If power supplies were that inefficient, then the computer is hotter - still toasts bread.

View power supplies from responsible computer companies. Those 'more than sufficient for all upgrade' power supplies are so much smaller. Because engineers use relevant numbers.

Or buy an inexpensive tool to learn what really exists - a Kill-A-Watt or something equivalent. Others did that to discover reality: https://forums.anandtech.com/thread...ge-while-browsing-these-forums.2307345/page-3
"What is your desktop power usage while browsing these forums?"

"Power consumption from the killawatt = 103 at idle. "
" a 40'' Sony from about a year ago, and that only uses about 50w."
"41 watts idle - 109 watts running Prime95"
"gtx460 and 3770k puts me squarely at 75w"
"115W idle, and 260W full load (CPU + GPU doing BOINC)."
"Web Browsing - 52W Playing Mechwarrior Online - 150W"
"all the 3 laptops I tested with my "kill a watt" stayed easily under 15w for very light load,"
"brisbane (65nm) athlon X2 at 2.4GHz (PSU around 75% efficiency), idle at 53w while loading heavy websites it could go even 20w over that, but most of the time it was around 60-65"

Did you go to the source for facts (ie use a Kill-A-Watt or something equivalent)? Or do what disciples of junk science always do - automatically believe a majority? Never take anyone's word for it. We, who do this stuff, always demand numbers and then confirm them.

 

[keenklee]

Nobody said anything about efficiency. Power supplies were once only 40% or 50% efficient. Today's must exceed 80% or violate national standards. None of that says why we tell a computer assembler to buy a 700 watt PSU for a system that rarely consumes 350 watts.

If power supplies were that inefficient, then the computer is hotter - still toasts bread.

View power supplies from responsible computer companies. Those 'more than sufficient for all upgrade' power supplies are so much smaller. Because engineers use relevant numbers.

Or buy an inexpensive tool to learn what really exists - a Kill-A-Watt or something equivalent. Others did that to discover reality: https://forums.anandtech.com/thread...ge-while-browsing-these-forums.2307345/page-3
"What is your desktop power usage while browsing these forums?"

"Power consumption from the killawatt = 103 at idle. "
" a 40'' Sony from about a year ago, and that only uses about 50w."
"41 watts idle - 109 watts running Prime95"
"gtx460 and 3770k puts me squarely at 75w"
"115W idle, and 260W full load (CPU + GPU doing BOINC)."
"Web Browsing - 52W Playing Mechwarrior Online - 150W"
"all the 3 laptops I tested with my "kill a watt" stayed easily under 15w for very light load,"
"brisbane (65nm) athlon X2 at 2.4GHz (PSU around 75% efficiency), idle at 53w while loading heavy websites it could go even 20w over that, but most of the time it was around 60-65"

Did you go to the source for facts (ie use a Kill-A-Watt or something equivalent)? Or do what disciples of junk science always do - automatically believe a majority? Never take anyone's word for it. We, who do this stuff, always demand numbers and then confirm them.

IMHO.
Isn't it good that I brought efficiency into the picture? Else, consumers may take it literally that, when not mentioned, could be 100% ?

So let's say I am to DIY a computer, do I based on the total wattage, or do I need to take into consideration of the various wattage the various rail of the PSU can supply ?
( Isn't it good again that I bring up something new in the discussion ? )

So I gathered that you're into numbers on PSU. That means all your computers PSU, in general, would be exactly 250W ?

You listed a whole chunk of information from the internet and you are also saying "Never take anyone's word for it". Now you should know why some may choose higher specs PSU because you can't test anything that you don't have ?

I usually want to sound quite nice one, if not, I will say something like

So, YOU ( your so call we ), whom always demand numbers and confirm them. Without taking anyone word for it, enlighten me ( or US ) how to determine the wattage of the PSU needed without having a PSU.

Which is why at times, like you said, I don't take your word for it. To me, and maybe others, your writing style makes things less comprehensible.

As a consumer, time is $. Doesn't make sense to find out everything - buy car need to know how a car work ?

P.S.
Did you go to the source for facts (ie use a Kill-A-Watt or something equivalent)? Or do what disciples of junk science always do - automatically believe a majority? Never take anyone's word for it. We, who do this stuff, always demand numbers and then confirm them. <-- Please do not question as if the whole world revolves around you.

 

[westom]

So let's say I am to DIY a computer, do I based on the total wattage, or do I need to take into consideration of the various wattage the various rail of the PSU can supply ?
...
You listed a whole chunk of information from the internet and you are also saying "Never take anyone's word for it". Now you should know why some may choose higher specs PSU because you can't test anything that you don't have ?

Only defined was a problem. In all technical work, solutions are a separate thought process that occurs only after a problem is first defined. The relevant expression is "Break a problem down into parts."

Watts says nothing useful. Again, the problem. We recommend buying a power supply that is double what is required because most all have no idea what is relevant. Yes, what is relevant is power provided by each rail. Or more accurately, amps for each DC voltage. Power supplies list those amps numbers. Numbers say why computers from informed (responsible) computer manufacturers have more than enough power from supplies with only half that power. And tend to be more reliable.

Another problem. Disk drives can be powered externally from a USB port. What is that wattage? Less than 2.5 watts. How many watts does a part picker program claim a disk drive needs? 10 watts. Specification numbers that are rarely known to and routinely withheld from computer assemblers. Another example of the point. Better informed computer assemblers should learn how much misinformation is provided or how little they are told.

Anyone can determine if a power supply is undersized using a digital meter and but a few minutes of labor. Or using other equipment. Most don't bother to do what is routinely done in computers from computer companies. Most do not know any of this due to so much basic knowledge and specifications that is withheld. Many then jump to (wildly speculate that) a supply is too small. A sufficient power supply for most all computers is 350 watts or less. And is selected by other, relevant spec numbers.

Why do informed consumers know what should be obvious? Computer is no where near so hot as to toast bread. Many computers, most of the time, only consume between 100 and 200 watts. Laptops (that would even get so hot as to sometimes burn legs) consumed less than 100.

Again, long before making any recommendations, one should know of misinformation from so many sources. And why that misinformation is widely promoted.

How many chassis fans are needed? Most all computers are perfectly fine with one 80 mm fan. Why then do so many computer assemblers install six fans? Computer assemblers are not taught to first define a problem before implementing a solution. Number of fans is easily calculated with a simple multiplication equation involving only watts and CFMs. Or one simply experiments (obtains numbers) to learn what is obviously too many fans.

Appreciate another problem. Simplest technical reality required seven paragraphs. Many eyes glazed over with only two. A problem so often found when a computer assembler automatically assumes he is computer literate. And does not learn about information intentionally not provided.

Assembling a computer does not save money. Especially if one assumes time is money. Assemble a computer to learn. Assembled computers tend to be less reliable for various reasons beyond scope of this discussion. For example, by missing essential functions. Among advantages of a custom built computer: forces one to learn. Some do. For example, one may eventually learn why comprehensive hardware diagnostics would have saved so much money and time (since those do not exist for custom computers). Unfortunately some learn nothing due to shotgunning. And my not confirmed what so much hearsay says.

Most have no idea why they are told to buy a 700 watt computer for a system that does not even consume 350 watts. Many also do not know why a 350 watt system needs a UPS maybe as much as 500 watts - that much oversized.

Another example of misinformation. Leaving a computer on means a computer consumes more electricity. Leave it on only when used intermittently during the day. Otherwise best for less energy consumption and for increased computer reliability: power off (shutdown or hibernate) when done. Numbers make that obvious.

 

[keenklee]

Only defined was a problem. In all technical work, solutions are a separate thought process that occurs only after a problem is first defined. The relevant expression is "Break a problem down into parts."

Watts says nothing useful. Again, the problem. We recommend buying a power supply that is double what is required because most all have no idea what is relevant. Yes, what is relevant is power provided by each rail. Or more accurately, amps for each DC voltage. Power supplies list those amps numbers. Numbers say why computers from informed (responsible) computer manufacturers have more than enough power from supplies with only half that power. And tend to be more reliable.

Another problem. Disk drives can be powered externally from a USB port. What is that wattage? Less than 2.5 watts. How many watts does a part picker program claim a disk drive needs? 10 watts. Specification numbers that are rarely known to and routinely withheld from computer assemblers. Another example of the point. Better informed computer assemblers should learn how much misinformation is provided or how little they are told.

Anyone can determine if a power supply is undersized using a digital meter and but a few minutes of labor. Or using other equipment. Most don't bother to do what is routinely done in computers from computer companies. Most do not know any of this due to so much basic knowledge and specifications that is withheld. Many then jump to (wildly speculate that) a supply is too small. A sufficient power supply for most all computers is 350 watts or less. And is selected by other, relevant spec numbers.

Why do informed consumers know what should be obvious? Computer is no where near so hot as to toast bread. Many computers, most of the time, only consume between 100 and 200 watts. Laptops (that would even get so hot as to sometimes burn legs) consumed less than 100.

Again, long before making any recommendations, one should know of misinformation from so many sources. And why that misinformation is widely promoted.

How many chassis fans are needed? Most all computers are perfectly fine with one 80 mm fan. Why then do so many computer assemblers install six fans? Computer assemblers are not taught to first define a problem before implementing a solution. Number of fans is easily calculated with a simple multiplication equation involving only watts and CFMs. Or one simply experiments (obtains numbers) to learn what is obviously too many fans.

Appreciate another problem. Simplest technical reality required seven paragraphs. Many eyes glazed over with only two. A problem so often found when a computer assembler automatically assumes he is computer literate. And does not learn about information intentionally not provided.

Assembling a computer does not save money. Especially if one assumes time is money. Assemble a computer to learn. Assembled computers tend to be less reliable for various reasons beyond scope of this discussion. For example, by missing essential functions. Among advantages of a custom built computer: forces one to learn. Some do. For example, one may eventually learn why comprehensive hardware diagnostics would have saved so much money and time (since those do not exist for custom computers). Unfortunately some learn nothing due to shotgunning. And my not confirmed what so much hearsay says.

Most have no idea why they are told to buy a 700 watt computer for a system that does not even consume 350 watts. Many also do not know why a 350 watt system needs a UPS maybe as much as 500 watts - that much oversized.

Another example of misinformation. Leaving a computer on means a computer consumes more electricity. Leave it on only when used intermittently during the day. Otherwise best for less energy consumption and for increased computer reliability: power off (shutdown or hibernate) when done. Numbers make that obvious.

Of which the answer which may be ?
Anyway, some of the questions not answered. Of course you are free to choose.

As you continue with your writing style, the earth continue to rotate.

 

[westom]

As you continue with your writing style, the earth continue to rotate.

When one does not like reality, then one blames others.

One who wanted to learn has already obtained a Kill-A-Watt to unlearn so much disinformation.

 

[keenklee]

When one does not like reality, then one blames others.

One who wanted to learn has already obtained a Kill-A-Watt to unlearn so much disinformation.

It should be, when one does not like reality, one chooses not to answer related questions asked. The ones who prefers reality, will specifically ask questions to the ones who do like reality of answering related questions, on purpose. The outcome is always the same.

While one can say one who wanted to learn has already obtained a Kill-A-Watt to unlearn so much disinformation, unknowingly to one, another could have already obtained a Kill-A-Watt to unlearn not only the "disinformation" but also more in broader perspectives. Being specific is important.

The questions remains, is total more important than combined ?

 

[enenyi]

...

Anyone can determine if a power supply is undersized using a digital meter and but a few minutes of labor. Or using other equipment. Most don't bother to do what is routinely done in computers from computer companies. Most do not know any of this due to so much basic knowledge and specifications that is withheld. Many then jump to (wildly speculate that) a supply is too small. A sufficient power supply for most all computers is 350 watts or less. And is selected by other, relevant spec numbers.

Why do informed consumers know what should be obvious? Computer is no where near so hot as to toast bread. Many computers, most of the time, only consume between 100 and 200 watts. Laptops (that would even get so hot as to sometimes burn legs) consumed less than 100.
...
How many chassis fans are needed? Most all computers are perfectly fine with one 80 mm fan. Why then do so many computer assemblers install six fans? Computer assemblers are not taught to first define a problem before implementing a solution. Number of fans is easily calculated with a simple multiplication equation involving only watts and CFMs. Or one simply experiments (obtains numbers) to learn what is obviously too many fans.


...

You probably have to re-read what you just typed.


Looking at wattage numbers coming from my digital watt meter (directly attached to my PSU's IEC power cable):

Threadripper 3960x (stock clocks) draws 120W on Windows desktop idle.
Threadripper 3960x (stock clocks) + GTX 980Ti (stock clocks) draws 190-210W on light workload (youtube video watching).
Threadripper 3960x (stock clocks) + GTX 980Ti (stock clocks) draws about 450W on regular gaming workload (FIFA 20).

So I'm "perfectly fine" with just 1 80mm fan? Sure, downclocking all 24 cores to 0.5GHz to prevent overheating at idle is possible, but it is sure a waste of money buying those cores in the first place. But to run my CPU chip at the manufacturer-rated 3.8GHz, I'm pretty sure more than just 1 single 80mm fan is required. If me using a DIY PC can experience this, what more other users buying high-end pre-built desktops experience power draw of "350 watts or less"? And sure, these may be a minority, hence the sweeping assumption does not hold.

And I haven't even gone to the whole "how much watts is enough" argument where most of your points, however formally phrased, stem from underlying assumptions made.

 

[westom]

So I'm "perfectly fine" with just 1 80mm fan?

One 80mm fan means air temperatures inside may be 6 degrees C higher than outside ambient air. That assumes no heat is transferred via other channels such as chassis cooling. A second fan (if in parallel; not in series) might reduce that temperatures by another 3 degrees.

 

[enenyi]

One 80mm fan means air temperatures inside may be 6 degrees C higher than outside ambient air. That assumes no heat is transferred via other channels such as chassis cooling. A second fan (if in parallel; not in series) might reduce that temperatures by another 3 degrees.

Maybe you wanna try doing CPU-intensive workloads (rendering, code compilation, etc) on a high-core count CPU before coming to any conclusion. Based on my own experience, no "6 degree C higher than ambient air" can be sufficiently cooled with just one 80mm fan. CPU temps already spitting out at least 20 degrees delta over ambient on such workloads, assuming other variables remain constant. Then there is the assumption on the fan speeds. How loud should the 80mm fan be? A few thousand rpms just to generate the required airflow to move the heated air out of the casing? Wouldn't a few fans operating in parallel achieve the same airflow efficiency at a lower noise threshold? And wouldn't the ambient air be heated up over time that "6 degrees over ambient" hold on a relative scale, but the absolute increase in temps be well over 6 degrees because ambient (your baseline) is also heating up? So many assumptions to make over these one-line statements, and other ppl have been pointing it out to you, but you keep shying away from addressing the underlying assumptions to your valid/invalid statements

(Edit: not just in this thread, but in the other thread(s) that u have walls of text on during reply).

 

[cscs3]

Only defined was a problem. In all technical work, solutions are a separate thought process that occurs only after a problem is first defined. The relevant expression is "Break a problem down into parts."

Watts says nothing useful. Again, the problem. We recommend buying a power supply that is double what is required because most all have no idea what is relevant. Yes, what is relevant is power provided by each rail. Or more accurately, amps for each DC voltage. Power supplies list those amps numbers. Numbers say why computers from informed (responsible) computer manufacturers have more than enough power from supplies with only half that power. And tend to be more reliable.

Another problem. Disk drives can be powered externally from a USB port. What is that wattage? Less than 2.5 watts. How many watts does a part picker program claim a disk drive needs? 10 watts. Specification numbers that are rarely known to and routinely withheld from computer assemblers. Another example of the point. Better informed computer assemblers should learn how much misinformation is provided or how little they are told.

Anyone can determine if a power supply is undersized using a digital meter and but a few minutes of labor. Or using other equipment. Most don't bother to do what is routinely done in computers from computer companies. Most do not know any of this due to so much basic knowledge and specifications that is withheld. Many then jump to (wildly speculate that) a supply is too small. A sufficient power supply for most all computers is 350 watts or less. And is selected by other, relevant spec numbers.

Why do informed consumers know what should be obvious? Computer is no where near so hot as to toast bread. Many computers, most of the time, only consume between 100 and 200 watts. Laptops (that would even get so hot as to sometimes burn legs) consumed less than 100.

Again, long before making any recommendations, one should know of misinformation from so many sources. And why that misinformation is widely promoted.

How many chassis fans are needed? Most all computers are perfectly fine with one 80 mm fan. Why then do so many computer assemblers install six fans? Computer assemblers are not taught to first define a problem before implementing a solution. Number of fans is easily calculated with a simple multiplication equation involving only watts and CFMs. Or one simply experiments (obtains numbers) to learn what is obviously too many fans.

Appreciate another problem. Simplest technical reality required seven paragraphs. Many eyes glazed over with only two. A problem so often found when a computer assembler automatically assumes he is computer literate. And does not learn about information intentionally not provided.

Assembling a computer does not save money. Especially if one assumes time is money. Assemble a computer to learn. Assembled computers tend to be less reliable for various reasons beyond scope of this discussion. For example, by missing essential functions. Among advantages of a custom built computer: forces one to learn. Some do. For example, one may eventually learn why comprehensive hardware diagnostics would have saved so much money and time (since those do not exist for custom computers). Unfortunately some learn nothing due to shotgunning. And my not confirmed what so much hearsay says.

Most have no idea why they are told to buy a 700 watt computer for a system that does not even consume 350 watts. Many also do not know why a 350 watt system needs a UPS maybe as much as 500 watts - that much oversized.

Another example of misinformation. Leaving a computer on means a computer consumes more electricity. Leave it on only when used intermittently during the day. Otherwise best for less energy consumption and for increased computer reliability: power off (shutdown or hibernate) when done. Numbers make that obvious.

Temperature part is very subjective. You cannot use the feel of leg, airflow to measure. Don't believe? Remove the CPU heatsink and use your finger to press on it then power on your PC. Let see how long you can remain your finger at the CPU chip!

Please also do not mix up maximum wattage vs actual usage. A computer equip with 700 watt power supply does not means it will use all the 700 watt but up to 700 watt (well, minus the efficiency which is around 80% to 90%). This means a 700 watt power supply, at most time may be able to use around 600 +/- watts. During the life spam, additional card/disk may be added or remove. So if at normal use say 350 watts. Does not means a UPS of 500 watts is good enough. Usually we buy a product to allow some additional use just in case. AND most important, after using it for sometime - will the product still perform as good?

Not to forget UPS runs on batteries. Something that have a life spam. Day one capable to run at max of 500 watt does not means it will be as good 1 years latter. Unless one is very particular, replacing these parts regularly to up keep equipment to day 1 condition.

 

[westom]

Maybe you wanna try doing CPU-intensive workloads (rendering, code compilation, etc) on a high-core count CPU before coming to any conclusion.

Apparently you never worked with systems that are first turned on in the morning to heat the room.

From numbers that were provided, the 80mm fan (which is running at a full 100 CFM) means 6 degrees C. If your temperatures increased 20 degrees, then your system is consuming over 1000 watts.

Or using quieter fans that run slower. Then one 80 mm fan would result in a 16 degree C temperature difference. The science is well proven.

If a computer was consuming anywhere near 700 watts, then one 80 mm fans would result in a 30 degree temperature increase. Obviously a computer is never getting that hot because PCs do not consumer anywhere near 700 watts.

Computers built by professional manufacturers typically only need one fan. Then internal air temperatures never exceed 85 degrees F in a room with fans operating quietly. Two fans or one fan operating at high speed means internal air temperatures remain in the high 70s. More than cool enough.

Unfortunately computer assemblers have no idea how to calculate any numbers. (So we tell them to buy a 700 watt PSU for a system that consumes less than 350 watts.) Temperature claims about the silicon die are irrelevant to air temperatures. (BTW, if one touches a semiconductor and does not leave skin, then it is not too hot.)

A 700 watt PSU must provide 700 watts constantly. Not 600 watts. But yes, some 700 watt PSUs cannot do what is required. They are marketing to consumers who make excuses rather than blame scam marketing myths. A 700 watt PSU must provide up to 700 watts constantly. Which means it is constructed to even provide more during short periods.

No problem. That 700 watt supply need only provide 350 watts or less. As demonstrated by heat so minimal as to not toast bread.

To market to same consumers, a UPS is made so cheaply that its life expectancy is three years. So that the UPS can provide sufficient power three years later (and for other technical reasons), a 500 watt UPS is recommended for the typical computer (that never consumes more than 350 watts).

A UPS, in facilities that cannot have outages, has a life expectancy of just under 20 years. They are not using a UPS that is marketed on price. They use a UPS marketed on specification numbers. Always consult spec numbers.

 

[enenyi]

Apparently you never worked with systems that are first turned on in the morning to heat the room.

No I have not, and I don't need to. If all computers in the world require the room to be heated before use then we have a problem. Not everyone needs to be in an industrial scenario to use a computer. Hence your assumption is not valid.

From numbers that were provided, the 80mm fan (which is running at a full 100 CFM) means 6 degrees C. If your temperatures increased 20 degrees, then your system is consuming over 1000 watts.

Again, assumption. In an industrial scenario, 100CFM is totally fine. In a work-from-home or office scenario, have you seen computers with 80mm fans pushing 100CFM winds? U know how much noise that fan will end up having? No simple equation can model the usage scenario.

Or using quieter fans that run slower. Then one 80 mm fan would result in a 16 degree C temperature difference. The science is well proven.

If a computer was consuming anywhere near 700 watts, then one 80 mm fans would result in a 30 degree temperature increase. Obviously a computer is never getting that hot because PCs do not consumer anywhere near 700 watts.

Assumption again. In this case, what kind of PCs are we talking about? Mini-itx PCs? Regular workstation PCs? High-end desktop PCs? Servers racked up in server rooms? Each PC has its intended purpose, hence its parts customised for that purpose. As such, no such thing as "PCs do not consume anywhere near 700 watts". Just take a high-end Intel CPU, an X299 motherboard, 2 RTX Titans (for machine learning), some fast storage, and you will break the 700W mark for usage (both sustained and short burst). If you are referring to rack-mounted servers, then obviously the power draw may be different because usually (not all) server rooms provide passive cooling to the components by way of high airflow, so there is not much need for server PSUs to draw such high power usage when someone else is providing the cooling. But the heat generated has to come from somewhere and go somewhere. And the numbers reflected will depend on the type of PCs we are talking about. Generalizing without stating underlying assumptions lead to pointless arguments.

Computers built by professional manufacturers typically only need one fan. Then internal air temperatures never exceed 85 degrees F in a room with fans operating quietly. Two fans or one fan operating at high speed means internal air temperatures remain in the high 70s. More than cool enough.

Again, assumption. Professional manufacturers == manufacturers of servers (Dell, HP Enterprise, Lenovo)? Or professional manufacturers == computer parts manufacturers like Asus, MSI, Gigabyte, etc? Or professional manufacturers == any computer manufacturer that sells pre-built computers and/or computer components on a professional basis? Without that quantification, the statement provided above has no added value to the argument.

Unfortunately computer assemblers have no idea how to calculate any numbers. (So we tell them to buy a 700 watt PSU for a system that consumes less than 350 watts.) Temperature claims about the silicon die are irrelevant to air temperatures. (BTW, if one touches a semiconductor and does not leave skin, then it is not too hot.)

Again, assumption. This time round, computer assemblers == professional manufacturers mentioned previously? Or referring to another totally different group? Do you tell server manufacturers to put in 700 watts PSU for less than 350 watts power draw? They will happily explain to you about redundancy for their systems (2x 350W PSUs).

A 700 watt PSU must provide 700 watts constantly. Not 600 watts. But yes, some 700 watt PSUs cannot do what is required. They are marketing to consumers who make excuses rather than blame scam marketing myths. A 700 watt PSU must provide up to 700 watts constantly. Which means it is constructed to even provide more during short periods.

No problem. That 700 watt supply need only provide 350 watts or less. As demonstrated by heat so minimal as to not toast bread.

Assumption (again). Which consumers? Buyers of servers from manufacturers like HP Enterprise, Dell and Lenovo? The narrative up till this point seems like so. Stating blatant facts like "A 700 watt PSU must provide up to 700 watts constantly" without linking it to the argument makes it look like some haphazard copy-paste efforts.

To market to same consumers, a UPS is made so cheaply that its life expectancy is three years. So that the UPS can provide sufficient power three years later (and for other technical reasons), a 500 watt UPS is recommended for the typical computer (that never consumes more than 350 watts).

A UPS, in facilities that cannot have outages, has a life expectancy of just under 20 years. They are not using a UPS that is marketed on price. They use a UPS marketed on specification numbers. Always consult spec numbers.

Finally, this is the part that makes me confused. Even though this is a thread discussing about UPS, did I at any point in time bring up UPS in my replies? Then why bring in UPS? I was targeting the underlying assumptions made in your statements, making some others in this thread rebutt the argument, but both not seeing the other party's points due to the underlying assumptions in the argument. Shows that either you do not bother to finish reading replies, or do not bother to quote properly when replying.