Will all of the yellow wires off the PSU be 12v? I have some WILD wiring to do yet, and I think I'm gonna pull my hair out if it's not...
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Will all of the yellow wires off the PSU be 12v? I have some WILD wiring to do yet, and I think I'm gonna pull my hair out if it's not...
I'd be willing to bet money on it, and I'm currently broke.
(And no, not from making bad bets. They'll all be +12v.)
yes, all yellow are 12v, orange are 3v, red are 5v, black is ground, blue is -12v, green gets shorted to ground to turn the PSU on, gray is a sense wire to make sure the PSU is on
FTFY ;)Quote:
Originally Posted by SXRguyinMA
But yes, all the yellow lines are 12V.
Most switching PSUs will feed all the ground/returns into a common point, usually immediately after the AC bridge rectifier and fuses. Some switching PSUs will feed the grounds into separate rails, so that they each "float" into associated discrete regulator stages (this allows tighter regulation without placing as much strain on the filter caps; effect is lower heat, better efficiency, higher part count, tougher engineering complexity, higher cost). Modular PSUs are almost always designed to accomodate a wider range of oddball device/power configurations, so they tend to be more suited for your purpose, Kayin.
Basically, if you have a non-modular PSU and it feeds black wires into different places then be careful to match the loads on your hot wires into them; don't join yellow (12V) wires off separate plugs unless the matching black wires on these connectors feed into the same place. If you pull 12V and 12V from two rails your grounds need to have the same balance whether you're powering one 24V or two 12V devices; this might be difficult to achieve. You especially don't want to bypass or spider any active power correction circuitry (which is typically sitting in a single part or logic board, though sometimes a weird distributed gestalt sort of feature).
We all know that modifying your PSU and operating it outside of consumer spec is risky, forbidden, voids the warranty, etc ... the reality is that there's a fair chance you'll somehow impede whatever "smart" load regulation circuitry is engineered into the PSU, either knocking your voltage range tolerances up a little or putting extra electrical strain (and heat) onto critical components (typically the rectifier or big caps). If it survives a few minutes/hours without smoking or blowing fuses while providing stable power at a decent load then you're probably safe ... it doesn't hurt to check PSU component temps before/after, running too warm will shorten PSU service life. It might be wise to stress-test under heavier than normal load (lots of drives or something), and it might be wise to do it with a non-precious platform (in case PSU regulation spikes out of range enough to cook the MBB).
I don't know if you're planning to use a 24V device or a 12V device than can pull twice the amps ... either way, you might consider modifying the device (instead of the PSU) so that it accepts two or more power plugs. A second PSU might be an option (though it might require shorting the PWR_OK pin and installing a PCI relay-switch or somesuch); a variant would just be a separate power supply (basically a modified wall-wart) which again might require some sort of switching relay.
If you're trying some experimental Krazy-Kayin hack to dump more juice into an OC'd GPU card (or whatever it is you're up to) then lol, you rock, best of luck, and you probably already know more about what the hell you're doing than I do.