I searched and found one answer but the links provided by Ravi no longer work...
I'm having a terrible time with my card reader, it can't read/find my SD card (Tried a few to make sure) and on occasion when it does find the card it takes forever to open folders/files?
Usually gives error saying (PCIE Card Reader - Not Responding)
PS! Running Win 8.1 on Dell Inspiron 15" 7537
This is the card reader driver:
Windows FAQs and OEM Downloads