High power passive 12V PSU

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

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High power passive 12V PSU

Post by boost » Tue Aug 23, 2011 2:39 am

I found a PSU for industrial and medical applications that deliver 25A at 12V passive and 30A with active cooling.
Can I run the 12V line into a 12 V Pico PSU AND run a graphics card's 6-pin and 8-pin power connector, i.e. Radeon 6950, directly from the 12V line?

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Re: High power passive 12V PSU

Post by multiplexer » Tue Aug 23, 2011 10:19 am

No, not really. The problem is in switching the power. You'd need to separately switch the 12V lines not passing through the picopsu as well. I did that in one of my builds using a P-mosfet with the gate stuck to the same switching signal going to another 12V switcher on the picopsu.

If you do not understand what I'm saying here, you should probably not do this yourself.

Also, as an aside, that big PSU, how well does it fare under no-load conditions? I think it will probably use a few watts when no current is being drawn. If you're using this arrangement for efficiency and silence, just beware that this could be a caveat for both (i.e. the unit will heat up when turned off).

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