Use overpowerd PSU due to better efficiency?
Posted: Wed Oct 23, 2013 12:11 am
Hi,
i am looking for a new power supply for my storage server - since it's on 24/7 it should be as efficient as possible.
I ended up with an Intel board an an E31230v3 as the Avoton based boards are still in low supply around here.
So doing the math:
Board + Processor + Ram + Raid Cards will likely be < 100 Watts (more like 40 on idle i hope)
Disks - Up to 16 -> max 160W, lets say 200 to be sure (load), max half of that on idle
So basically i need a high efficient power supply with max 300W on 100% load (and o/c the required Amperes for the 12V rail)
Now the other side - 40W + 100W =~150W idle, rather less since i probably wont use that many disks all the time.
I quote the power supply fundamental post here;)
"
Even so, Is Higher Power Better?
Without getting into technical details, the nature of a switching power supply is that it delivers as much power as is demanded by the components. This means that when installed in a PC whose components require 200W, a 400W PSU and a 250W PSU will each deliver 200W. Does this mean the 400W is coasting while the 250W is struggling? Not if they are both rated honestly and if they have the same efficiency. If one has lower efficiency than the other, then it will consume more AC to deliver the same power to the components, and in the process, generate more heat within itself. As long as there is adequate power, higher efficiency is the key to cooler, quieter PSU operation.
The main benefit of higher power PSUs is when the airflow in the PSU is deliberately set very low in order to minimize noise. This usually means the PSU components will run hotter. If all other things are equal, a higher rated PSU may be a better choice in such an application because its parts are generally rated for higher current and heat than a lower rated model.
"
So am i right in thinking that to pick a proper power supply i need to look at my power usage and then select the PSU which can supply the desired wattage (range) with the highest efficiency even if is extremely overrated?
I am not taking the price into consideration i know, but i guess it wont be too much difference between a high efficiency 400W and a high efficiency 700W PSU since the masses tend to use higher wattage than needed.
So:
Is the price the only difference at the same efficiency level at my usage range?
Assuming i dont care about the price and i find a power supply with 1000W rating and efficiency of 93% at 10%+20% (100w/200W) is it more efficient than a PSU rated 400W with 92% at 10/20/50% (40W,80W,200W) ?
Or will i be mislead since i cant actually compare the real supplied wattage/efficiency levels (i.e. i cant compare them watt by watt since all i get is ranges, here i dont know the efficiency of the 1000W PSU at 4%,8 usage to compare that to the 400W)?
Thanks,
Thomas
i am looking for a new power supply for my storage server - since it's on 24/7 it should be as efficient as possible.
I ended up with an Intel board an an E31230v3 as the Avoton based boards are still in low supply around here.
So doing the math:
Board + Processor + Ram + Raid Cards will likely be < 100 Watts (more like 40 on idle i hope)
Disks - Up to 16 -> max 160W, lets say 200 to be sure (load), max half of that on idle
So basically i need a high efficient power supply with max 300W on 100% load (and o/c the required Amperes for the 12V rail)
Now the other side - 40W + 100W =~150W idle, rather less since i probably wont use that many disks all the time.
I quote the power supply fundamental post here;)
"
Even so, Is Higher Power Better?
Without getting into technical details, the nature of a switching power supply is that it delivers as much power as is demanded by the components. This means that when installed in a PC whose components require 200W, a 400W PSU and a 250W PSU will each deliver 200W. Does this mean the 400W is coasting while the 250W is struggling? Not if they are both rated honestly and if they have the same efficiency. If one has lower efficiency than the other, then it will consume more AC to deliver the same power to the components, and in the process, generate more heat within itself. As long as there is adequate power, higher efficiency is the key to cooler, quieter PSU operation.
The main benefit of higher power PSUs is when the airflow in the PSU is deliberately set very low in order to minimize noise. This usually means the PSU components will run hotter. If all other things are equal, a higher rated PSU may be a better choice in such an application because its parts are generally rated for higher current and heat than a lower rated model.
"
So am i right in thinking that to pick a proper power supply i need to look at my power usage and then select the PSU which can supply the desired wattage (range) with the highest efficiency even if is extremely overrated?
I am not taking the price into consideration i know, but i guess it wont be too much difference between a high efficiency 400W and a high efficiency 700W PSU since the masses tend to use higher wattage than needed.
So:
Is the price the only difference at the same efficiency level at my usage range?
Assuming i dont care about the price and i find a power supply with 1000W rating and efficiency of 93% at 10%+20% (100w/200W) is it more efficient than a PSU rated 400W with 92% at 10/20/50% (40W,80W,200W) ?
Or will i be mislead since i cant actually compare the real supplied wattage/efficiency levels (i.e. i cant compare them watt by watt since all i get is ranges, here i dont know the efficiency of the 1000W PSU at 4%,8 usage to compare that to the 400W)?
Thanks,
Thomas