Power Supply Info

[NaughtyDog321]

So I am a moderate pc builder but still don't know everything. One thing I really never got was power supply wattage. I know that there is obviously a minimum requirement but is there a maximum? What stops me from going out and buying a 1000 watt PSU instead of getting a 750 watt. Go big or go home right?

[Tha Joker]

There isn't a thing as too much power. They will all output the amount of wattage needed in the system (  obviously if the PSU can handle it ). Really just the efficiency and reliability the bigger watt PSU's have.

[NaughtyDog321]

2 minutes ago, Tha Joker said:

Really just the efficiency and reliability the bigger watt PSU's have.

I hear like JayzTwoCents saying efficiency a lot with PSU's, What does he exactly mean?

[Tha Joker]

6 minutes ago, NaughtyDog321 said:

I hear like JayzTwoCents saying efficiency a lot with PSU's, What does he exactly mean?

In theory a more powerful Power Supply should be able to handle loads better. So if for example your computer has a 500watt Power Supply and the wattage is close to 500, it's going to be less efficient in putting out the power ( putting more stress on the Power supply to keep the components going ). But if there was a 750watt or a 1000 watt, it doesn't have to work as hard to keep the same computer working. So it's efficient in the quality of work it's projecting on your machine.

 

Less work... better performance - High watt Power Supply

More work... good performance - Medium Watt Power Supply

A lot of work... bad performance - Low watt Power Supply.

 

I would suggest anywhere between 200+ watts of extra room when purchasing a Power Supply... in theory you will probably upgrade parts.. so giving yourself more room to play with will save you money in the long run. opposed to needing to purchase a new Power Supply.

[AskTJ]

On 06/06/2018 at 12:22 PM, NaughtyDog321 said:

I hear like JayzTwoCents saying efficiency a lot with PSU's, What does he exactly mean?

You want to buy power supplies with 80+ ratings, preferably 80+ Gold.

 

The Corsair CX power supplies are great value power supplies. They have 80+ Gold ratings and are very cheap. They are Tier 3 on the official power supply list, making it one of the best value power supplies out there.

[NaughtyDog321]

Sweet thanks man, you were a tremendous help!!!

[NaughtyDog321]

I have been looking at those power supplies for a while, they seem really good.

 

[Tha Joker]

Just now, NaughtyDog321 said:

Sweet thanks man, you were a tremendous help!!!

 I suggest anything from EVGA that is 80+ Gold... they are a great company with amazing customer support. I personally have the EVGA 750watt Supernova Series.

[NaughtyDog321]

Nice, I'll check it out! I am personally looking for a new power supply for my build.

[NaughtyDog321]

What about platinum certified PSUs?

 

[mariushm]

So to answer all your questions.

 

A power supply has a simple job : it takes power from the mains and converts it to the voltages needed by your computer. 

It will only produce as much power for the components inside, as the components require.

The value on the power supplies (500w , 850w, 1000w) represents the maximum amount of power the power supply can produce and send to components if needed. If the components in your PC don't require that much, then the power supply will simply not produce that power. So you can use power supplies rated for much higher wattage with computers that don't use a lot of power, without any issue (from an electrical point of view)

 

As with any conversion, there are some losses. When AC voltage is taken from the mains and converted into DC voltages, some power is lost in the form of heat. Because of this, a power supply will always take more power from the mains socket than what it delivers to components.

That's what efficiency refers to on the power supplies:  if the power supply is 90% efficient, that means that out of 100% of the power going into the power supply, only 90% went to components that requested power, and 10% was lost in the form of heat mostly.

 

So there's several "standards" of efficiency, 80 Bronze, Gold , Platinum, Titanium .. the more "expensive" the metal in the title, the more efficient the power supply will be, but it will also be more expensive.

 

So for example, a 80 Bronze power supply only needs to be at least 82% efficient, while a 80 Gold power supply needs to be at least 87% efficient in ordered to be labeled like that. 

 

As an example, if the components in a PC need 100 watts, than that means a 80 Bronze power supply will actually take 100w x 100/82 = ~ 122 watts from the mains socket and those 22 watts will be lost as heat,  while a Gold power supply will only take 100w x 100/87 = ~115 watts, so only 15w will be lost as heat.  This means the Gold efficiency power supply is slightly cooler, and that often means the manufacturer of the power supply can use more silent fans or fans that spin slower to maintain the power supply in the right range of temperatures, and that's good for your ears.

 

 

 

Now, power supplies are not perfect, that conversion is not done the same at any amount of output power. The circuit converting the power will not have the same efficiency if it only delivers 100w to components, or 1000w to components. All these circuits have a peak efficiency when they're most efficiency and as the power consumed by components is further away from that peak, the efficiency of the circuit goes down a bit. 

 

In most power supplies, this peak is somewhere around 60-70% of their maximum output power... so for example, a 500w power supply may be 90% efficient at 400w, but only 88% at 500w, or only 85% at 100w. So for this reason, it's often recommended not to use power supplies rated for too high wattage if your computer doesn't consume so much power.

For example, a 650w power supply will be fairly inefficient if your computer is only used for office work, and would be a waste of money to buy such a big power supply.

 

The higher the quality of the components inside, the smaller that variation in efficiency is... so for example even with Gold efficiency power supplies or better, the efficiency tends to lower by a only a very small amount once you go over that peak, in practice it's not worth thinking about it... for example a psu would be 96% efficient at 500w, and 95% efficient at 800w ... that 1% is super small and not worth thinking about.

 

It does matter with cheaper Bronze rated power supplies.

 

 

 

[Stefan Payne]

54 minutes ago, NaughtyDog321 said:

What stops me from going out and buying a 1000 watt PSU instead of getting a 750 watt. Go big or go home right?

Price, noise, more damage when something goes wrong.

 

43 minutes ago, Tha Joker said:

In theory a more powerful Power Supply should be able to handle loads better. So if for example your computer has a 500watt Power Supply and the wattage is close to 500, it's going to be less efficient in putting out the power ( putting more stress on the Power supply to keep the components going ). But if there was a 750watt or a 1000 watt, it doesn't have to work as hard to keep the same computer working. So it's efficient in the quality of work it's projecting on your machine.

You need to look at the Efficiency curve and not just assume something...

And also what Difference are we talking about 1-2%??

 

Quote

Less work... better performance - High watt Power Supply

More work... good performance - Medium Watt Power Supply

A lot of work... bad performance - Low watt Power Supply.

No, not true. 

A PSU isn't an engine, what is true for the motor in your car is not for electronics devices.

And usually higher wattage units, especially the 1kW+ ones tend to be louder than the 550W ones...

 

You need at least different heatsinks for the larger one to be quieter and such...

Quote

I would suggest anywhere between 200+ watts of extra room when purchasing a Power Supply...

For what exactly?!
The Power consumption for normal parts didn't increase w/o OC.

 

Quote

 

in theory you will probably upgrade parts.. so giving yourself more room to play with will save you money in the long run. opposed to needing to purchase a new Power Supply.

Yeah and that didn't happen in the last decade or so. Except for the HEDT Plattform, of course.

But for normal Desktop/Mobile it didn't increase.

 

If we go by price - you could get an i7-920 for 200 bucks or less at a certain time - then it drastically decreased.

Also the non-K Intel CPUs the Power Consumption decreased drastically, for example an older i7-2600 had a TDP of 95W while newer ones like the i7-8700 only have 65W TDP.

Also AMD got rid of the 140 and 125W TDP Class with Ryzen.

 

As for Graphics cards, lets look at a GTX 470 wich was available for around 200 bucks or so.

 

And now look what we can get for the same price - and its a 75W TDP 1050ti or a 1060 - wich is around 150W.

The GTX 470 had a TDP of 225-250W...

 

So that should be enough to prove you wrong...

[Tha Joker]

30 minutes ago, Stefan Payne said:

Price, noise, more damage when something goes wrong.

 

You need to look at the Efficiency curve and not just assume something...

And also what Difference are we talking about 1-2%??

 

No, not true. 

A PSU isn't an engine, what is true for the motor in your car is not for electronics devices.

And usually higher wattage units, especially the 1kW+ ones tend to be louder than the 550W ones...

 

You need at least different heatsinks for the larger one to be quieter and such...

For what exactly?!
The Power consumption for normal parts didn't increase w/o OC.

 

Yeah and that didn't happen in the last decade or so. Except for the HEDT Plattform, of course.

But for normal Desktop/Mobile it didn't increase.

 

If we go by price - you could get an i7-920 for 200 bucks or less at a certain time - then it drastically decreased.

Also the non-K Intel CPUs the Power Consumption decreased drastically, for example an older i7-2600 had a TDP of 95W while newer ones like the i7-8700 only have 65W TDP.

Also AMD got rid of the 140 and 125W TDP Class with Ryzen.

 

As for Graphics cards, lets look at a GTX 470 wich was available for around 200 bucks or so.

 

And now look what we can get for the same price - and its a 75W TDP 1050ti or a 1060 - wich is around 150W.

The GTX 470 had a TDP of 225-250W...

 

So that should be enough to prove you wrong...

What power supply's are you purchasing that make noise, lmfao? If you read his questions, I answered them. No one is getting into efficiency curves and price per performance. It's pretty simple to understand. If your machine is needing 500watts, buy a 750watt PSU, simple as that.

[Stefan Payne]

1 minute ago, Tha Joker said:

What power supply's are you purchasing that make noise,

Some are louder in the 1000/1200W version than the 550W ones...

For example my Leadex II 650/750W or EVGA G2/G3, compare the lower wattage ones to 850W and up...

The lower wattage ones are more quiet than the higher wattage ones.

Just look it up!

 

1 minute ago, Tha Joker said:

No one is getting into efficiency curves and price per performance.

But THAT is what you need to do to give good recommendations. 

 

1 minute ago, Tha Joker said:

It's pretty simple to understand. If your machine is needing 500watts, buy a 750watt PSU, simple as that.

That's just false and not true at all.

Why do you believe that?!

 

+50% capacity for what exactly?!

And what machine needs 500W?!

When I need to put a second graphics card in a PC to get around 500W secondary...

 

For that you need a HEDT or 750€+ Graphics card...

[Tha Joker]

3 minutes ago, Stefan Payne said:

Some are louder in the 1000/1200W version than the 550W ones...

For example my Leadex II 650/750W or EVGA G2/G3, compare the lower wattage ones to 850W and up...

The lower wattage ones are more quiet than the higher wattage ones.

Just look it up!

 

But THAT is what you need to do to give good recommendations. 

 

That's just false and not true at all.

Why do you believe that?!

 

+50% capacity for what exactly?!

And what machine needs 500W?!

When I need to put a second graphics card in a PC to get around 500W secondary...

 

For that you need a HEDT or 750€+ Graphics card...

What you aren't understanding is.. he is a new builder. This all means literally nothing to him. He isn't purchasing big expensive parts that will be overclocked and need to consume so much power. You need to relax lmao. All my examples were very easy to understand. You aren't going to continue to upgrade your PSU when you don't have to. Buy more for later. You don't have the same Power Supply wattage as what your build is asking for.

 

Stop quoting me and trying to go back and forth, I won't continue to reply to you.

[Stefan Payne]

1 minute ago, Tha Joker said:

What you aren't understanding is.. he is a new builder. This all means literally nothing to him. He isn't purchasing big expensive parts that will be overclocked and need to consume so much power.

Yes and for what should he waste money on a PSU that has double the Wattage he actually needs?!
Where's the benefit?!

 

You should stop recommending stuff that wastes the money of others.

All he needs is a good 450-550W PSU, not a 750W one wich in many cases has a higher spinning fan than the lower wattage one.

You need to look at the model you are recommending, not just claiming that "more Watts = Better", that's just bullshit.

You want a better PSU first, if you wa nt the Efficiency, get a Platinum one instead, not a 750W.

 

The Platinum one gives some advantages, in some cases a lower RPM fan, while the 750W one gives you a higher RPM fan.

 

1 minute ago, Tha Joker said:

All my examples were very easy to understand.

What examples?!
And they are wrong. If you need 500W, get a 550W. 750W is a waste of money, if you do not need the wattage.

It doesn't give any benefit and in some cases causes more trouble than its worth as well.

 

1 minute ago, Tha Joker said:

You aren't going to continue to upgrade your PSU when you don't have to.

Yes and if you have to, you do.

 

the ATX specification was introduced 22 Years ago, in 1996. 

The Probability that there are changes in the next 10 years that render the PSU useless and incompatible is pretty high given that the AT "Standard" only lasted about 10 Years.

 

1 minute ago, Tha Joker said:

Buy more for later.

...when the Power Consumption of the components decreased in the last ~10 Years wich I have proven with Links.

Totally makes sense.

And when you need _TWO_ higher end graphics cards to go over 500W...

Did I mention that I use _TWO_ 7970GHz/280X on a Ryzen 1700X System?? With a 550W PSU as well (Cougar GX-F)

 

1 minute ago, Tha Joker said:

You don't have the same Power Supply wattage as what your build is asking for.

Why? For what reason?

You get what you need, everything more is wasted money you can invest in better things like a better quality fan. ie a Noctua NH-D15 instead of a normal PSU.

 

You want quality, not quantity!

 A Platinum unit makes more sense when you want the Efficiency than getting +200W

A higher Quality unit makes more sense than getting +200W.

 

There is just no reason to get a 750W+ PSU for a single CPU/GPU System.

 

And looking at your system, if you went for the 550W EVGA G2 instead, you'd gotten a quieter PSU...

 

[Stefan Payne]

1 hour ago, NaughtyDog321 said:

What about platinum certified PSUs?

 

You can't generalize much about PSU.
There are some good quality PSu, there are some shitty ones, regardless of the efficiency. 

A Platinum certified PSU only offers around 2% higher efficiency - but nothing more when the same layout is used.

In general:

• You don't buy a Wattage you don't need to -> no advantage, waste of money..
• If you still want to invest in the PSU, get a better one.
• If you want a quiet PSU, you have to look for a quiet one. There is no generalisation in this area (well, except that be quiet PSU are rather quiet, EVGA are not).
• Getting a higher wattage unit won't give you a less noisy unit, it just gives you higher wattages and in many cases higher wattage means higher rpm fan
• You don't need to spend 100€ or more for a good quality PSU, if you don't want/need a modular one, you can get a good one for 70€ or so,

BUT: Don't expect it to last 10 Years or longe and buy it with the thought in mind that the ATX Specification might be gotten rid of at any time and that you might be able to use the PSU with the next system but not the one after that.

 

[EsaT]

6 hours ago, Tha Joker said:

There isn't a thing as too much power. They will all output the amount of wattage needed in the system (  obviously if the PSU can handle it ). Really just the efficiency and reliability the bigger watt PSU's have.

How about you "put your money where your mouth is" and get one of these for your car?

http://www.emma-maersk.com/engine/Wartsila_Sulzer_RTA96-C.htm

After all you never know if you sometime have to tow the whole city!

 

Without optical drives, separate sound card etc that typical average gaming PC is idling below 50W.

And if you put that into 5% load point of PSU efficiency is going to be from dozen years in the past and instead of at best half dozen watts being wasted to heat by PSUs there's easily 15W turned into heat to warm room.

 

And as you advertise just getting lots of those cheap marketing watts instead of quality during gaming that turns easily to PSU wasting 30 watts as heat instead of 15W.

http://www.silentpcreview.com/A_Better_Way_to_Compare_PSU_Efficiency

"For higher power loads, Bronze vs. Gold is pretty clear cut. The average Bronze rated PSU uses 10W more at 100W output, 15W more @ 200W, and 25W @ 300W."

And comparing that oversized marketing watts 80+ Bronze PSU to better sized 80+ Platinum would show more difference.

 

5 hours ago, Tha Joker said:

He isn't purchasing big expensive parts that will be overclocked and need to consume so much power.

So why are you advertising getting more cheapest marketing watts is good?

[NaughtyDog321]

In a nutshell right now I have a 450 watt power supply, I want a very nice, fully modular, quiet power supply, regardless of the price. Btw thank you all for the super helpful advice, there is way more to power supplies than I thought lol