Originally posted by Yamota Thanks, I did not know this. Seems weird to advertise a certain power but not able to deliver it.
The multi-rail PSUs that were popular a few years ago were the worst at this:
You got like 4 rails, and if you added them all up, you got the rated wattage, but no individual rail could pull anything useful and it was easy to overload just one rail without going over the entire PSU rating.
And you can still do that today, even though we've gone back to single rail designs, we still have multiple voltage taps (+5 Vdc, +5 Vsb, +12, -12, +3.3), and each of those have amp limits, and the sum of those is what they print on the box.
jdnewell hit on it perfectly - it's more about quality of power, since your taking wall voltage (110/220 VAC, 50/60Hz - depending on where you live), and turn that into steady and reliable DC voltage, where a fluctuation as little as 0.05 Vdc can have a big impact in stability, and multiply that sensitivity if your overclocking.
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The multi-rail PSUs that were popular a few years ago were the worst at this:
You got like 4 rails, and if you added them all up, you got the rated wattage, but no individual rail could pull anything useful and it was easy to overload just one rail without going over the entire PSU rating.
And you can still do that today, even though we've gone back to single rail designs, we still have multiple voltage taps (+5 Vdc, +5 Vsb, +12, -12, +3.3), and each of those have amp limits, and the sum of those is what they print on the box.
jdnewell hit on it perfectly - it's more about quality of power, since your taking wall voltage (110/220 VAC, 50/60Hz - depending on where you live), and turn that into steady and reliable DC voltage, where a fluctuation as little as 0.05 Vdc can have a big impact in stability, and multiply that sensitivity if your overclocking.
It's also not uncommon for resellers to outright lie. It's true, there's only a handful of OEM manufactureres, and most of these are rebranded - and it's not uncommon for what is sold as a 750W PSU by Brand A is the exact same power supply sold as Brand B rated for 450W.