# QuestionWhat does advertised PSU wattage mean?

##### Reputable
Suppose I have a 600 watt 80 plus rated PSU with exact 80% efficiency (hypothetically). Does that mean I get (750 multiply.8)=600 watt or (600 multiply .8)=480 watt.

#### Zerk2012

##### Titan
Suppose I have a 600 watt 80 plus rated PSU with exact 80% efficiency (hypothetically). Does that mean I get (750 multiply.8)=600 watt or (600 multiply .8)=480 watt.
Actually it is saying if your pulling 100 watts from the wall then your getting 80 watts to the PC.

#### USAFRet

##### Titan
Moderator
Suppose I have a 600 watt 80 plus rated PSU with exact 80% efficiency (hypothetically). Does that mean I get (750 multiply.8)=600 watt or (600 multiply .8)=480 watt.
This is HIGHLY dependent on the specific PSU.

A janky one may state
"600W, 80 Plus Bronze"

And actually only deliver 352 watts.

#### Nigel Spike

##### Honorable
As a math example it would be 600W / 0.8 = 750W. Power from PSU = 600W. Power pulled from wall = 750W.

##### Reputable
Actually it is saying if your pulling 100 watts from the wall then your getting 80 watts to the PC.
I am aware of that but my confusion is about the rated power. Is the PSU rated power i.e. the wattage written on the box 100 or 80 in this case.

##### Reputable
This is HIGHLY dependent on the specific PSU.

A janky one may state
"600W, 80 Plus Bronze"

And actually only deliver 352 watts.
It is from thermaltek. I don't think they might be junky as no name generic ones

##### Reputable
As a math example it would be 600W / 0.8 = 750W. Power from PSU = 600W. Power pulled from wall = 750W.
I'm leaning this to be the one I am looking for because in the product specifications page it says max output 650 watt and peak output 780 watt. But I'm too noob in this matter. Is 750 watt that you pointed out the peak wattage in that hypothetical 600 watt PSU? Or 780 watt in my case the maximum my PSU can pull until it breaks or triggers protections?

#### USAFRet

##### Titan
Moderator
It is from thermaltek. I don't think they might be junky as no name generic ones
"thermaltek" was not mentioned in the original question.

Nor is "thermaltek" an indicator of "completely not junk"

#### rolli59

##### Titan
I'm leaning this to be the one I am looking for because in the product specifications page it says max output 650 watt and peak output 780 watt. But I'm too noob in this matter. Is 750 watt that you pointed out the peak wattage in that hypothetical 600 watt PSU? Or 780 watt in my case the maximum my PSU can pull until it breaks or triggers protections?
PSU std rating is always their max sustained DC output rating built in protection allows them to handle short spikes of higher output before triggering protection. So if it is rated 600watts that is what it can deliver combined over all rails and voltages. How manufacturers calculate that differs with most modern quality PSU capable to deliver most all of that on the + 12 volt rail/rails but many low quality units add up 5volts and 3.3volts that see very little usage today and give them higher rating than deserved.
So back to your 600watt unit it can deliver total of 600watts of DC power to your components but when it does that then it is pulling 750 watts of AC power from your wall socket.

#### Zerk2012

##### Titan
I am aware of that but my confusion is about the rated power. Is the PSU rated power i.e. the wattage written on the box 100 or 80 in this case.
You asked a general question that they were no accurate answer to and I was correct with my answer.
Then you link the PSU that has absolutely nothing to do with your question.

https://en.wikipedia.org/wiki/80_Plus

Power supplies are so poorly regulated you can call one 600 watts and it will go up in flames if you pull 400 watts from it. Most of the quality 600 watt PSU's can at least for a short burst deliver well over the rated watts for example ratted for 600 watts but when actually tested did not trip out any safety to shut it down until it hits say 700 watts.

A quality 600 watt PSU that can in the perfect world actually deliver 600 watts to the PC @80% efficiency will do just that deliver 600watts to the PC but draw 720 watts from the wall socket. The 120 watts extra from the wall is lost converting the power from AC to DC and turns into heat. (this is when it actually takes 600 watts to run your PC it only will put out what is needed for the load on the PC)

For getting the Gold rating that can also be very deceiving, You can produce 10000 power supplies and check every one and the one that performs the best send it in to get your certified ratting although the 9999 rest of them never was at that level. EDIT then their the crap companies that will just say 80% bronze and nobody cares so nothing is ever checked.

To put it in car terms you can produce 1000 mustangs all the same right off the assembly line and one of them will outrun the others and one will get better gas mileage.

The power supply you linked is about the best you can get from that brand but is still nothing I would buy, recommend or use.

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##### Reputable
You asked a general question that they were no accurate answer to and I was correct with my answer.
Then you link the PSU that has absolutely nothing to do with your question.

https://en.wikipedia.org/wiki/80_Plus

Power supplies are so poorly regulated you can call one 600 watts and it will go up in flames if you pull 400 watts from it. Most of the quality 600 watt PSU's can at least for a short burst deliver well over the rated watts for example ratted for 600 watts but when actually tested did not trip out any safety to shut it down until it hits say 700 watts.

A quality 600 watt PSU that can in the perfect world actually deliver 600 watts to the PC @80% efficiency will do just that deliver 600watts to the PC but draw 720 watts from the wall socket. The 120 watts extra from the wall is lost converting the power from AC to DC and turns into heat. (this is when it actually takes 600 watts to run your PC it only will put out what is needed for the load on the PC)

For getting the Gold rating that can also be very deceiving, You can produce 10000 power supplies and check every one and the one that performs the best send it in to get your certified ratting although the 9999 rest of them never was at that level. EDIT then their the crap companies that will just say 80% bronze and nobody cares so nothing is ever checked.

To put it in car terms you can produce 1000 mustangs all the same right off the assembly line and one of them will outrun the others and one will get better gas mileage.

The power supply you linked is about the best you can get from that brand but is still nothing I would buy, recommend or use.
"A quality 600 watt PSU that can in the perfect world actually deliver 600 watts to the PC @80% efficiency will do just that deliver 600watts to the PC but draw 720 watts from the wall socket." This is the answer I was looking for. I know it depends. I wanted to know what does that mean. Thank you.

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