psu power draw?

GraveYard · 5 Dec 2011 at 22:38

will a 1000w power supply draw the same amount of power as a 650w in the same rig???

might be a stupid question sorry if it is...

lrlcr · 5 Dec 2011 at 22:41

only if the efficiencies at the load are the same, which is relatively unlikely.

Venares · 5 Dec 2011 at 22:42

Yes

Give or take a few Watts.

lrlcr · 5 Dec 2011 at 22:55

I really significantly depends on the load and efficiencies. It could easily be 100w difference.

GraveYard · 6 Dec 2011 at 16:23

ah ok cheers lads...

weird_dave · 6 Dec 2011 at 17:11

I doubt there will be 100W difference and here's why.
At the low power (idle) end where the efficiencies will vary more between supplies, you're not drawing much power anyway, so even a huge difference still isn't much.
At the higher end you'll be in the flatter area of efficiencies which might be, say, 10% different as an example. Even pulling 500W, that's only a 50W difference in power draw.

Also, thee's no telling which one will draw more, I suspect that the 1000W supply will actually be more efficient, they generally need to be due to heat.