See subject. MSI z77a-gd55 board, windows 8. I had them working (charging my phone) with the PC in sleep mode and/or off, but it no longer does and for the life of me I cannot figure out why or what setting I may have switched.
Maybe the power options got switched? Have you tried checking them out in:
Control Panel\Hardware and Sound\Power Options\Edit Plan Settings\Advanced Power Settings\
Under USB settings I have "USB selective suspended setting" disabled. I don't put my computer to sleep but I made sure to change my settings to pretty much always allow my desktop to have max power any time.