It could be a bum motherboard or a bum card reader, do your front panel ports assuming you have them (You said you have an old case?) work? Test the reader in another system and test your motherboard with other devices
Hey, I bought a memory card reader from bestbuy and it did not work I tried all usb ports no luck. Went back and exchanged it for a new one and it worked perfectly, so I suggest you try a new internal card reader.