Here is the thing I used that el-cheapo AC/DC adaptor for. 2 12cm casefans I placed next to my screen for personal cooling purposes, this can prove to be very valuable during summertime as the temperature sometimes rises over 35 degrees Celsius in my room, aaaahhhh cooling.
I used the powerswitch of a busted Cisco 1601R to be able to turn the fans on and off. The fans are taken from an old IBM rackmount server and are both on one powercord. The fanguards were already placed on them.
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