Sorry for the delay in replying. I've never had a problem with card readers connected to the built-in USB ports not being recognized after sleep (I use an Imation FlashGo! and another that's name escapes me now). My G4 won't wake up when anything (an external USB 2.0 CD-RW or a USB 2.0 card reader) is connected to a SIIG USB 2.0 PCI card and powered up. It will sleep and wake up just fine if the CD-RW is first powered down. The card reader is always on, so I disconnect it after each use.