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I have been considering replacing the CPU Power Supply on my 2002 Gateway machine. The original OEM power supply maximum rating was 240 watts. My Graphics card has been upgraded to one that recommends a power supply of 270 watts minimum. I would like a power supply with a power supply rating of 400 watts or higher.

In searching the internet for power supplies available for my specific case, I have only found one recommended replacement that fits my case size and attachment bracket which is offered at It is Model: FSP ATX-300GU - 300 Watt ATX Power Supply

I cannot seem to locate/identify a power supply rated at 400 Watts or better that will fit my case without modification of the case attachment method and which includes the outdated 6-pin AUX motherboard connector.

Can anyone assist in ientifying a power supply rated at 400 Watts or higher that is of the same dimensions and connectors of the recommended replacement listed above that will work without modifying the method of attachment in my case?

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here's a 400w ATX PSU with a 6-pin AUX connector, said to be working with most Dell / HP computers:

Athena Power 400 Watt 20+4 pin Micro PS3 ATX Power Supply w/ 6-pin AUX

the dimensions are as follow:


6" Wide X 3.5" Tall X 5.5" Deep

Athena AP-MPS3ATX40

6" Wide X 3.25" Tall X 4" Deep

the lower heigth and depth of the Athena shouldn't constitute a problem. as in fact the Athena is recommended if you click the link 'Need more power? Try this 400 watt power supply as an upgrade to this 300 watt power supply.' on the ATX-300GU product page.

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The Athena PSU Dimensions are: • 3.25" X 5.75" X 4" (H x W x D) • 4" Depth is Reduced Size to fit special cases My original PSU and the recommended replacement I found for the FSP ATX-300GU dimensions are: 6" Wide X 3.5" Tall X 5.5" Deep I don't believe the Athena unit will work with my ATX case bracket that holds the unit in place. It seems the bracket is not adjustable to different front to back demensions of the power supply. Perhaps I am missing something. Any suggestions are appreciated. – Jerry Sep 21 '09 at 22:54

I have a computer from the same era, (2001 I think) and it has the bracket on the back that you are referring to. This is a non-standard mounting arrangement, as you have already determined. Not all is lost!

My case(and probably yours) also has screw-holes for standard ATX power supply mounting.

If you can see the screws in this photo from Foner Books. If you see those holes, you can buy any standard power supply. The back bracket should be removeable, so as long as the PSU is short enough to fit behind your CD-ROM, you'll be fine.

There is a caveat: Some older systems require a -5V lead on the 20-pin ATX motherboard connector, this is the "white-wire". Make sure whichever PSU you purchase includes this -5V lead if your existing PSU has it.

Here is another diagram and more info about the ATX form factor.


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