Weird power supply issue

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??
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More about weird power supply issue
  1. Did you ensure that the motherboard is properly grounded to the case with the little elevators?
  2. Yes I did. It is. It will power up just fine without the memory card reader plugged in. when i plug that in, its completely dead. no power.
  3. The patient says, "Doctor, it hurts when I do this." "Then don't do that!"

    Some PSUs will shut down if they detect a short.
  4. Lol. yeah well i need to use that leg!!!
    Yeah i'll see if i can rma it. could be a short. thanks
  5. Are you sure you're not plugging in the card reader to the wrong header on the motherboard? That would cause a short. I've seen people plug USB devices into the HD audio pins.
  6. 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.
  7. 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.
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