I have this issue too. The realtek usb driver for the card reader is draining power in standby. I fixed this by doing those steps: (the english terms might not be fitting 100%, my windows has a different language)
- Find Realtek USB 2.0 Card Reader in device manager
- Right click on it and select "update driver"
- Select "Search on my computer"
- Choose "Select from a list of available drivers on my computer"
- Select "USB-mass storage device" instead of "Realtek USB 2.0 Card Reader"
- click on "Continue"
If you do this the icon in the explorer for the SD card changes to the standard icon windows uses for drives. This is also a good indicator if the driver was changed by windows automatically. This happens from time to time especially on major spring or fall
updates.
So far I didn't notice any problems with the default USB mass storage device driver. But the power drain in standby is gone and I can keep my SD card attached at all times.
Hope that helps somebody.
Regards