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Power Suppy Question

  • Power Supplies
  • Power
  • Components
Last response: in Components
November 12, 2012 6:25:42 PM

Hey all. Does a 700W PSU and a 500W PSU same brand in the exact same system draw the same amount of power/energy use?

Basically I want to upgraded my PSU first to a 700W and want to know if I put it in my current system will it become less energy efficient.

More about : power suppy question

a b ) Power supply
November 12, 2012 7:03:03 PM

PSU's pull only what is demanded from them plus whatever they need to supply that power.

The more efficient the PSU the less power it needs to do it's job.

So a newer, mor efficient 700w PSU could end up pulling less power from the wall outlet than an older, less efficient PSU.
a b ) Power supply
November 12, 2012 8:24:05 PM

if you upgraded to a low end 700w vs a high end 500w, you would be losing more than what you will be gaining

anyways, efficiency of the unit is determined by how much power you are drawing. power supplies tend to be most efficient when the load is around 40-60% of the rated output of the unit

therefore for a 500w, assuming it can output 500w on the 12v rail, will be most efficient when the system is drawing 250w

for a 700w, assuming it can supply 700w on the 12v rail, it would be most efficient at around 350w.

if you are not hitting those marks, efficiency will drop, therefore consuming a bit more power