After my desktop wakes from sleep mode, one of my HD drives "disappears" and is no longer available nor is it seen listed under "My Computer". An additional one, not the one with the OS (of course), is there after the PC wakes. I am running Win 7, 64 bit, installed on an ASUS M3N-HD/HDMI MB, with 8G RAM. The HD disk is a SATA, WD. Is this happening to anyone else?