Power Supply - Dual Voltage vs Single Voltage!

[DreamerSpawn]

I am trying to choose a new PSU. My dilema is something that I'm not used to. PSU's with 'dual voltage'. My question is this: With dual voltage, what is the purpose? For example:

Let's say you have a dual voltage PSU. I'm going to use the "MSI TurboStream 600W BTX 600Watts Power Supply 90 - 264 V Safety" PSU. See Full Details Here

Here are the 'dual voltage' specs:

+12V1@22A,+12V2@22A

Now, does this mean it totals up to 44A (duh, I'm pretty sure it doesnt...just need to know for sure)?

Many are going to ask what kind of system this is going on:

CPU: AMD Athlon XP 2800+
MOTHERBOARD: DFI Lan Party NFII Ultra B
VIDEO CARD: 256mb 8x AGP
HARD DRIVES: (2) 300 Gig IDE

Please help me decide. I'm having a VERY tough time finding PSU's with single voltage...and if so, deciding what is the proper AMPERAGE?

ANY help would be MUCH appreciated.

 

[DreamerSpawn]

Also, some opinions about the following PSU would be MUCH appreciated:

APEVIA (ASPIRE) ATX-AS500W-BL ATX12V 500W Power Supply


See, I'm looking to spend no more than $100 on a PSU (MAYBE $120)....and I need something that is going to last a while. I am ordering from newegg, since that's where I'm getting my tower from (ordering both at same time for shipping cost reasons).

 

[imported_RedStar]

read this thread:

http://forums.anandtech.com/messageview...atid=27&threadid=1815673&enterthread=y

(splitting 12v rail ..other similiar terms...dual rail...multi rail )

 

[pkme2]

PSUs to Avoid

The MSI has very little written up on it. Just basic stuff. I always try to checkout the weight of a PSU.
The weight tells me the quality of the power supply. Manufacturer's know by listing the weights is a clear indication of how the unit is built.
My Seasonic and Enermax are quite hefty in weight.

How to buy a PSU

The lightweights should be avoided at all costs. (usually weight is about a pound), while the same wattage in a quality PSU is about 1.8 lbs. or more. Better materials add heft to construction.

 

[Howard]

It's just one voltage, actually (+12V).

 

[Yellowbeard]

Originally posted by: DreamerSpawn
Also, some opinions about the following PSU would be MUCH appreciated:

APEVIA (ASPIRE) ATX-AS500W-BL ATX12V 500W Power Supply


See, I'm looking to spend no more than $100 on a PSU (MAYBE $120)....and I need something that is going to last a while. I am ordering from newegg, since that's where I'm getting my tower from (ordering both at same time for shipping cost reasons).

Aspire is not known for quality PSUs. I would suggest reading here: Jonny Guru

He tests very thoroughly so you can find PSUs in your price range and see how they did. Also, the Corsair HX520 is within the budget range you listed and has a 5 year warranty.

 

[DreamerSpawn]

What I mean't actually, was I'm having trouble deciding what Amperage (not voltage....corrected that). Bad night when I posted. Was getting frustrated.

 

[DreamerSpawn]

Okay, can anyone SUGGEST a power supply from newegg that is in about the 500w capacity that would do good on my system and last a while? Again, a $100-$120 limit. Please help guys. Thanks. I feel like an idiot cause I don't know about the brand or such on many power supplies....but this dual voltage thing REALLY throws me for a loop. I am thinkin that if it has two +12 leads, and both are at 22a, then it's simply a 22a psu. Correct? Confusing sometimes. I just need some help choosing a reliable psu for the system I am building.

 

[imported_RedStar]

seriously read the link i posted above...

you will find gems like

"What?!? But 18A plus 18A is 36A? Like the +3.3V and +5V rails I just mentioned, +12V rails are not additive. You can load each one up to 18A, but you can?t load them both up to 18A. "

everything and i mean EVERYTHING is explained by the guru of power himself! ))

 

[Zepper]

Actually the "dual voltage" mentioned is on the AC side, not on the DC side. Some PSUs have a switch for whether you have 110 or 220V AC in your house others have auto ranging AC compatibility. This automatically adapts to your AC - no switch needed and can also compensate for variations in your line voltage to make your PSU relatively immune to AC side disturbances. That feature usually accompanies active Power Factor Correction which makes your PSU a "friendly" load to the power system. If I can be so bold, I'd suggest clicking on the link in my Sig - I just happen to have a fine PSU for sale that has the auto-ranging AC, active PFC and a single +12 rail of 32 Amps.

And the apevia PSUs aren't that good in genera.

.bh.

 

[Effect]

Originally posted by: DreamerSpawn
Okay, can anyone SUGGEST a power supply from newegg that is in about the 500w capacity that would do good on my system and last a while? Again, a $100-$120 limit. Please help guys. Thanks. I feel like an idiot cause I don't know about the brand or such on many power supplies....but this dual voltage thing REALLY throws me for a loop. I am thinkin that if it has two +12 leads, and both are at 22a, then it's simply a 22a psu. Correct? Confusing sometimes. I just need some help choosing a reliable psu for the system I am building.

What's the Silverstone ST50EF-Plus going for at Newegg these days?

When it comes to finding out how much amperage a PSU has on the 12V rails, don't bother looking at the amperage on each rail; there's no magic formula for finding their combined output. Generally, your best bet is to click on over to the manufacturers website, and look for a total power output on the 12v rail (may sometimes be in wattage, in which case divide by 12).