best psu for my vid card

troymscott

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i need some help understanding how PSU distribute power i know the card i want evga 512-P3-N841-AR 8800gts (G92) is power hungry. It says i need +12 Volt current rating of 26 Amp Amps, now if there is more than one 12v rail do I add up the amps for each rail?

if it helps here are the PSU's I am considering

Antec NeoHE 550 High Efficiency 550W Power Supply

Enermax ELT500AWT/ELT500AWT-DXX Liberty 500W Power Supply

Corsair HX Series CMPSU-520HX 520W Power Supply Retail
 
What you need to find out for your PSU is the number of watt supplied to the +12v rail. You take that number and divide it by 12 to get your amps. When you have multiple rails, the max amps they give you are what each rail can sustain without the others being loaded.

As an example lets use the Corsair HX520 you listed. That unit has 480 watts supplied to the +12v rails. Take that and divide it by 12 and you get 40 amps. That unit can sustain 40 amps across all of the rails.

Personally, I like the Corsair HX series. They are made by Seasonic which is a very reputable name in PSUs. So of those, the HX520 would get my vote.
 

ZOldDude

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Apr 22, 2006
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Get a PC Power & Cooling 610.
One large rail very well regulated,that is -constant rated- (not surge) @ 49Amps on 12V with 40C air being blown into it.

$119 USD dirrect from the makers website.
 

IndigoMoss

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All of those PSU's will be more than adequate for what you want, but I'd say you'd save money with the Antec NeoPower. It is highly efficient and does a great job of providing power to all of your components. Power is getting more and more expensive now a days and a good efficient power supply will help save money on that. Since it's in your budget, I'd get that.

I wish I could get a nice efficient PSU, but unfortunately I'm a student and I don't have much money, so don't call me a hypocrite for using my Thermaltake TR2 430w
 

bildo123

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Ditto here man, I built a very nice budget system powered by a $30ish (After Rebate) Thermaltake PurePower 500W PSU. Says it has 14A 1st rail and 15A 2ed rail. I run a e2180 OC to 3Ghz and an 8800GT @ 700/1990. It's wicked quite and I never had a hiccup. The only other things on the rail are 1 74GB raptor and a dvd-burner. I never planned on SLI so this PSU hit the spot and I believe I made out pretty good at that.

Here's the PSU: http://www.newegg.com/Product/Product.aspx?Item=N82E16817153052&Tpk=500w%2bpurepower
 

Oh SoS

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The best bang for your buck right now is available at fry's...I just bought one of these from the store (not the website) at the same price:
http://shop4.outpost.com/product/4806800?site=sr:SEARCH:MAIN_RSLT_PG

And it's modular!

However, note the comments from "Paul" at this thread:
http://www.motherboardpoint.com/t162412-8800-gts-pcie-power-connector.html
>
>Your first concern, would be whether the power supply
>has enough amps on +12V, to power everything.
>
>The 2x3 PCI Express connector here, is used to carry about 6 amps,
>in round numbers. Some more current also flows through the PCI
>Express slot connector pins (roughly 3.5A).
>
> http://www.xbitlabs.com/articles/video/display/msi8800gts-640_6.html
> http://www.xbitlabs.com/images/video/msi8800gts-640/8800gts_full.gif
>
>Even one pin on the PCI Express 2x3 connector can carry six amps.
>AFAIK, the PCI Express 2x3 is from the same family as the main
>power connector (either 20 or 24 pin), and uses the same kind of
>pins.
>
>If I was purchasing an adapter for myself, I would use the
>one with two Molex connectors. That gives you the equivalent of
>two of three 12V pins. Which should be enough to do the job, and
>do it safely from the connector's perspective."
>
If you're planning to go SLI, you might want to get a beefier supply than even the Raidmax...some things I've read are recommending at least 1000W supplies to support the 8800 series (which I think is where the 26A number came from), but frankly, I don't think that's really necessary.
 

Oh SoS

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I knew there was a catch...

3.2.4. Power Limit / Hazardous Energy Levels

Under normal or overload conditions, no output shall continuously provide more than 240 VA under any conditions of load including output short circuit, per the requirement of UL 1950/ CSA 950/ EN 60950/ IEC 950.

—ATX12V Power Supply Design Guide, version 2.2