how many watts?

PSUs: The source of DC power for all components in the PC & often a big noise source.

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how many watts?

Post by n604 » Tue Jan 16, 2007 1:03 pm

I wanna get a Seasonic S12 power supply for this pc:
4x SATA II drives
2x X1400 video cards (running 3 or 4 monitors)
3 or 4 case fans

How many watts do I need?
How many is too little?
how many is too much?


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Post by Rusty075 » Tue Jan 16, 2007 1:28 pm

The X1400 isn't available as a stand-alone graphics card. It's a mobile-only part. Do you mean X1300 maybe?

Either way, you've skipped the most important part of the system spec from a PSU sizing point of view: the CPU.

The CPU choice is what will really determine what size PSU you need. Optical drives are trivial power users - anytime it is running at full speed the rest of the system won't be. There's no realistic way you could be running the CPU and GPU at 100% while burning a DVD and accessing every single HDD. Same with case fans...their impact on power use is just too tiny to worry about, 4 of them might add up to 10 watts max.

For 4 3.5" drives figure a max of around 60 watts.

A pair of X1300's would at a theoretical maximum consume about 60 watts as well, although if you're running multiple monitors there's no software app in the world that will max out the cards' 3D mode while spanning monitors. Two X1600's would max out at about 80 watts.

So far you've got 60 watts for HDD's, and 60-80 watts for GPU's. Unless you're planning on running a 190 watt CPU, even the smallest S12, the 330 watt model, would be plenty of power.

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Post by n604 » Tue Jan 16, 2007 2:26 pm

thanks for the help

right now the CPU is a p4 540 3.2ghz
but i'm gonna be upgrading to a core duo 6400 ...

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Post by SnooP » Tue Jan 16, 2007 3:17 pm

Core duo uses a lot less power the P4. Anyways seasonic s12 330w or 380w is plenty, apparantly the 380w model is quieter. go with them :)

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Post by six4withafro » Thu Jan 18, 2007 9:01 pm

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Post by n604 » Thu Jan 18, 2007 9:45 pm

excellent link
thank you

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Post by EsaT » Thu Jan 18, 2007 11:36 pm

six4withafro wrote:this will tell you
That tells mostly BS.

This gives much more realistic numbers:

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