Question about PSU MAX power.

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z_unit
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Joined: Fri Oct 22, 2004 7:40 am

Question about PSU MAX power.

Post by z_unit » Fri Oct 22, 2004 7:52 am

I see this on many psu's and i am curious for example for this
Image
420W psu how come that +3.3V, +5V, +12V = 400 W and -5V, -12V, 5VSB = 28W if psu is only 420 W and not 428W, why?


And in http://www.ocztechnology.com/products/psuSpec.pdf spec there is some "Peak load (60secs) 620W", does it mean its power on 0-25*C (just before it heat up)?[/img]

Rusty075
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Post by Rusty075 » Fri Oct 22, 2004 9:23 am

At the top of this forum there's a Sticky titled Sticky: # MUST-READ FAQ for System Advice Forum #

Read it, and the Power Supply Fundamentals article linked within.

The answer to your question is in there, along with lots more information.
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z_unit
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Post by z_unit » Sun Oct 24, 2004 3:03 am

Rusty075 wrote:At the top of this forum there's a Sticky titled Sticky: # MUST-READ FAQ for System Advice Forum #

Read it, and the Power Supply Fundamentals article linked within.

The answer to your question is in there, along with lots more information.
Dont see how Sticky: # MUST-READ FAQ for System Advice Forum # can answer my question, but i started to read Power Supply Fundamentals before i post, just have no finished yet ;) i am not american and i find this review using to complicated language in comparison with other review sites. I dont mean i dont understand it, but my unerstandability is kinda low at 02am in the morning, so i desided to read it some other time.
I'll let you know if i find answer there.

Tephras
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Post by Tephras » Sun Oct 24, 2004 11:20 am

You can probably find answers to your questions here.

z_unit
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Post by z_unit » Sun Oct 24, 2004 10:45 pm

Tephras wrote:You can probably find answers to your questions here.
Nope i did not, i am not electrician i dont care how power run in my pc.

meglamaniac
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Post by meglamaniac » Mon Oct 25, 2004 12:31 am

Well if you want to know the answer to your question you'll have to learn a bit - the physics isn't that complicated, it's the sort of thing you'd learn top end of GCSE or lower end of A-level (if you're in the UK).

You can't ask an electronics question and expect the answer not to involve electronics!

z_unit
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Post by z_unit » Mon Oct 25, 2004 5:20 am

Guess what i am not in uk :P and not in school anymore to.
I dont mind to learn some basic stuff about electronic, but knowing not how current runs insode of wires is just useless to me.

sthayashi
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Post by sthayashi » Mon Oct 25, 2004 9:06 am

Eh, what exactly is the question here?

Why numbers don't necessarily add up? I can't tell you that. Outright lies is the best I can tell you.

As for the peak load of 620W, basically that's more or less to inform you that it CAN handle that level load for a short period of time. This is somewhat useful if you have a lot of hard drives, especially old huge ones. Depending on the drive, they can draw 10 times more power upon spin up than they can on.

I have a computer that draws 60W at idle, and 112W at full power. However, it has 6 hard drives in there, 2 of them old SCSI beasts (you'll break your foot if you drop the drive on it). I've measured it, and on startup I've seen it draw as much as 300W!!! Were I a REAL sysadmin, this might be useful information to know. So, OCZ is kindly informing you that it can handle a little more power than what it's rated for, but not for any great length of time.
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