I get the gest of what you want, but there isn't one that I know of. HOWEVER, a typical PSU, jumpered to always be on when AC plugged MAY provide a simple solution. If there is one, maybe costly, test equipment.
http://pcsupport.about.com/od/insidethepc/tp/atx-pinout-power-supply.htm
http://www.duxcw.com/faq/ps/ps4.htm
http://www.gweep.net/~prefect/gallery/main.php?g2_itemId=20024
In jumpering, alot depends still depends on the quality of the PSU. Since, this isn't the intended purpose outside of the PC, you take your chances/risks.
tada -----Willy ![]()
Does anyone know if there is a "Dunlop DC-Brick Multi-Power Supply"-like device for PC peripherals? (the "Dunlop DC-Brick Multi-Power Supply" replaces power bricks for musicians) To replace the wall warts and bricks with a single supply?

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