Weird power supply issue

love_my_comp

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Jan 27, 2010
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Hello. I bought a new case for my home pc and put it together yesterday. in the previous case everything worked fine but it was a little cramped so i bought a bigger one. i put it all together yesterday and i couldn't get the motherboard to power on. i thought maybe it was the power switch connection, but my motherboard has a power button built on to the chasis and even that didn't work. Also the LED light on the motherboard was not illuminated. I checked my connections, the voltage on the psu, everything. I unplugged everything but the motherboard and it fired right up. after plugging back my connections one at a time i found the culprit. i have a ultra md2 media card reader that takes a power source. i was running this with the exact same power supply in my last case. With everything but the motherboard plugged in and this it still doesn't run so i know its not a wattage issue. If i have the LED lights illuminating but the pc is off and i plug this in, the LED shuts off and the PC wont power on. The only thing that has changed is the case. Also my psu is making a grinding noise but i believe that is just the fan and possibly unrelated. Any ideas??
 

vanekl

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Dec 6, 2009
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Keep in mind that the PSU may be incorrectly detecting the short. It's not automatically the card reader's fault. I'm not an EE so I don't know how to test this without switching components.
 

love_my_comp

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Jan 27, 2010
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Well actually the memory card reader isn't plugged into any usb ports at the moment. i disconnected everything to test. There is a seperate power (standard like a cd rom power) connection on the memory card reader. that was what i was referring to when i said plugging it in killed power to everything.