[SOLVED] More watts bad?

UnstopableAj101

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Jul 4, 2016
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I was going to get a nzxt e500 but the e850 is on sale for cheaper than the e500.
Would this be bad to use a 850w psu even though I don’t need all that power? Also would the 850w use more electricity than the 500 watt because I don’t want a higher electricity bill.
 
Solution
While @Metal Messiah. is correct, I feel like he is missing the one point that does contribute to your energy bill. (Though, like I said it isn't much.)

The higher wattage PSU will only draw what it needs, but it will likely need more energy to provide the power it needs. But by no means will it hurt anything, except like I said maybe $2-3 per year on your energy bill.

Let me explain..

If you only need 250W for your system, and you have two power supplies with the same efficiency curve relative to their load percent; the 500W would be more efficient over the 850W. Because the 500W unit will draw 278W (~90% efficiency) to push the 250W needed for your system, and the 850W unit will draw 288W (~88% efficiency) to push the...
No, it would not be bad. A lot of times higher wattage PSUs of the same make/model are made with better quality components. It could have a lower efficieny than the lower wattage unit at your given power usage, but your electricity bill might be $2 to $3 higher over the course of a year. That's not much.

How much is the E850? Both power supplies are over priced from what I can tell. But at least they come with a 10 year warranty.
 

UnstopableAj101

Honorable
Jul 4, 2016
21
0
10,510
No, it would not be bad. A lot of times higher wattage PSUs of the same make/model are made with better quality components. It could have a lower efficieny than the lower wattage unit at your given power usage, but your electricity bill might be $2 to $3 higher over the course of a year. That's not much.

How much is the E850? Both power supplies are over priced from what I can tell. But at least they come with a 10 year warranty.
It is 110 on Newegg
 
No, that PSU won't raise your electricity bill, assuming they have the same 80 PLUS efficiency. The system will still use/pull only the maximum wattage required, regardless of whether you have 500 or 850 Watts PSU.

Wattage number is not always important. The quality and the make matters. The main concern is the "quality" of the power, the quality of the components used/CAPS, as well as the total AMP drawn on the +12V RAIL (output), the efficiency under load, "ripple suppression", among other factors.

The total wattage number of any PSU is not always really the most important deciding factor, primary concern is the 'quality' of power it produces, and the total capacity of the 12V source etc.

And no, the extra power won't go wasted, it just won't get fully utilized.

Let me explain------------> If suppose you have a 500W PSU installed on any RIG, then that does not mean that it will always draw the full wattage/500 W.

Nope....... The amount of power drawn is determined by the number of components on that rig/computer, and how much they actually require. The amount of power drawn will only be equal to what is required, and not more.

Suppose, if all the components of a rig require 400 W to run, then the "load" on the PSU will be 400 W, and hence the power draw of that particular PC will always be 400 W (depending on the efficiency obviously), regardless of whether a 500 Watt or a 1000 W PSU is installed. PSU efficiency is a different matter though, as how well the PSU converts the AC power it receives from the outlet, to DC.

Any electricity which is not converted from AC to DC, is given off as heat. A PLATINUM certified PSU might help you save a little on your electricity bill, over a year, though this depends on many other factors as well. Because any high quality Tier 1 platinum certified PSU is rated for at least 90% efficiency at 20% load, 92% at 50% load, and 89% at 100% load (just a rough estimate).
 
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While @Metal Messiah. is correct, I feel like he is missing the one point that does contribute to your energy bill. (Though, like I said it isn't much.)

The higher wattage PSU will only draw what it needs, but it will likely need more energy to provide the power it needs. But by no means will it hurt anything, except like I said maybe $2-3 per year on your energy bill.

Let me explain..

If you only need 250W for your system, and you have two power supplies with the same efficiency curve relative to their load percent; the 500W would be more efficient over the 850W. Because the 500W unit will draw 278W (~90% efficiency) to push the 250W needed for your system, and the 850W unit will draw 288W (~88% efficiency) to push the 250W needed. At only a 25-30% load the 850W unit would be less efficient. But maybe you require more than 250W?? And I would say 10W difference in energy draw isn't that much, especially when the 850W unit allows for bigger upgrades over the next 10 years.

What are your system specs?
 
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Solution
This isn't a server farm OK, if you cannot afford to pay an extra $5 over the course of a year, then you shouldn't really be buying this system.
It's a pointless arguement.
Sure, if he has 100 of these doing something then that $500 may need to be lower, but again if he's buying 100 of them, again it's still neglible.

Let's not all get hung up on the efficiency, we know efficiency is nice, but quality IS the only thing that really matters, as any Quality PSU has a half decent effiency.
 
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It's a technical forum. I'd expect technical answers.
Then you are crap out of luck, because it doesn't need to be technical, it needs to be practical with some technical information (which has been provided)
This doesn't deserve an indepth technical answer.
It comes down to one thing.

If he buys the more powerful PSU, it may cost him an extra couple of dollars over an entire year. There is no need to complicate this issue at all, because it's not warranted. If the OP wants to get technical, then he can ask.
 
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Would this be bad to use a 850w psu even though I don’t need all that power?
Building a reliable system doesn't happen by accident, or luck. You need to do some informed selection of system components.

Add-up the total power (measured in Watts) required by the system that you have plans to build.

Double that number.

Buy a power supply that provides output power in accordance with that doubled number.

If your system will draw 425 Watts, you should be buying an 850 Watt power supply for that system.

You will derive two immediate benefits from this:
1.) You will not be operating the power supply at it's maximum designed output.
2.) You will be operating the power supply at, or very close to, its peak efficiency.