My PC does not wake up from sleep or hibernate. When attempting to wake the pc runs but the monitor is blank (yellow led=off). The computer is in a coma state, unreactive to any keyboard activity. I have to turn the main power switch off on back panel in order to recover operation on the next boot up. If I power down by holding the front panel switch for 3 seconds the next boot up results in a coma state.
Sleep and hibernate have always been know to be unstable. It was a huge mistake, by MS, to have even put it as an option.Don't use it. There is a big button on your monitor that you can push to turn it off.