Power Supply Eff

[Becks2k]

What powersupplies have the highest efficiency?

The enermax say the get a min of 72% eff at full load, anythin beat that?


Also, how much does load effect efficiency?

Run a powersupply with 1/2 its max load, does it get better or worse eff than at full load?

 

[FlowerMan]

Why do you need to worry about efficiency? What's your setup? What do you have in your case that you have to worry about efficiency? I've got 2 enermax's for a total of 761W Running a PIII-750@900, 3 HD's, 2 CDROM's, 6+ fans, and a GF3. No problems here

I would imagine efficiency would be inversely proportional to the amount of load put on it.

 

[Becks2k]

If I'm going to buy a powersupply, might as well get one that'll run the coolest... I wnat to put a la1, or less, in it. I found some powersupplies that say 60%, some that say 70%, the 70% one would make 25% less heat, thats like free cooling hehe.

Trying to think about how to make a quiet computer.. xmas is soon =D


--edit---

oh yea ' would imagine efficiency would be inversely proportional to the amount of load put on it. "

yea thats what i figured too, but ya never know hehe also wonderin if it changes alot

PCPower and cooling powersupplies... their 300w+ ones say "70%" while their 200w ones say 65 or 60

Wondering if thats the mostly because of difference components or less power.

 

[FlowerMan]

Power supplies do not create much heat when compared to a CPU or GPU. Maybe even compared to an HD. Whatever pitiful case fan they have in them will be enough to cool themselves off. IMO, a PS's fan should only be cooling itself. Don't depend on it to cool your entire case (like some people do!). Running fans at 7V or less can work miracles when it comes to fan noise.

 

[Becks2k]

PSs can create some heat... not that it gets added to the system or soemthing, but they still make some heat... if you'd use 300watts and it gets 70%eff thats means it takes ~428watts, 300 get outputed 128watts get turned to heat.

Most harddrives put off less than 10watts of heat... well I was looking at 5400rpm drives, no doubt 7200/10k/15k are gonna be hotter.

I'm not trying to use the powersupply to keep the case cool... i just wnat it to keep itself cool. Most powersupplies have fans that are 35+cfm.... pcpowerncooling's "ultraquiet" 400w ps makes 38dBa of noise I wanna put in a 20dBa/26CFM fan in there... tho it'd be louder than 20dBa from turbulance in the powersupply, but a;gleh anyways hehe

 

[FlowerMan]

Have you ever felt the exhaust of a PS's fan? Its not very hot, if hot at all. Granted, some of the POS generic ones may run hot, but Enermax, Antec, and Sparkle dont really get that hot. I'd estimate that my Enermaxs' 80mm fans are pushing about 10-20CFM, not loud at all. The air exhausted is still cool. I say get a nice Enermax 330+W and stop worrying

 

[Damascus]

<< PSs can create some heat... not that it gets added to the system or soemthing, but they still make some heat... if you'd use 300watts and it gets 70%eff thats means it takes ~428watts, 300 get outputed 128watts get turned to heat. >>



If a 300W PS is 70% efficient, doesn't that mean that it
outputs 210W?

 

[Becks2k]

"I say get a nice Enermax 330+W and stop worrying "

but my gf just went to bed! i gotta do something!

"If a 300W PS is 70% efficient, doesn't that mean that it
outputs 210W? "

PSs are rated by how much power they put out, not how much they use.

 

[FlowerMan]

<< 128watts get turned to heat. >>



Trust me, 128W of heat is not being dissapated by the PS's heatsinks and the puny 80mm fan. If it were, you'd be feeling a whole lotta heat being exhausted from your PS, and the PS would prolly fail sometime soon. I mean, there are engineers that work on this $hit so we dont have to. They sell a unit to perform under normal conditions satisfactorily. Like I said, Don't worry about it. Wake your gf up and start talking to her about her wardrobe...

 

[Becks2k]

128watts would IF you used 300. It might spike to that when harddrives are spinning up, or cdrom drives, or whatever... but using a constant 300watts isn't likely.

The air coming out of my powersupply is hotter than the air coming outa my pal6035, the heatsink has less air coming out of it too. 800tbird@1.1 1.9v, thats bout 50watts?

"They sell a unit to perform under normal conditions satisfactorily. "

Yea they have enough cooling to keep it running, but I'm hurting that cooling alot. I'm taking a fan out and puttin one with bout 1/2 the airflow, they didn't design it for that.. but that doesn't mean it won't work.

Okay nevermind hehe I'll get a stinkin enermax like everyone else nite all

 

[ColdFlare]

dude my antec 400 watt psu blows hot air out, i've been meaning to rewire the fan inside so it doesnt use the stupid thermal control, or switch the fan and solder the wires together so i dont lose the 2 pin power connector