I'm glad you have total success with windows sleep, but unfortunately I'm not so lucky. About 10% of the time when I wake from sleep, the monitor never turns on...the power light just keeps blinking like it has no video signal. Most of the time, I can just push the power button on the front of the computer to put it back into sleep, then wake it up again a second time and all is fine. But every now and then, it seems to be hard locked after the wake, as I cant force it back to sleep, shut it down with keyboard shortcuts, or anything. I have to do the 4-second-power-button trick to force it off and do a full reboot (and then I've lost the state of all my apps, along with anything that was unsaved.
I assume it's a video card issue, and have tried updating the nvidia drivers multiple times, but no luck. For the record, it's not a hardware compatability issue, because it actually worked flawlessly for the first couple years after I built it. And I never update drivers unless I'm trying to resolve a specific issue (which is rare), so this issue wasn't related to a driver update. So it started either in relation to a windows update that broke it, or some system configuration that was randomly corrupted somehow.
Also, on my work laptop, I've also twice had an issue where the hibernate (as opposed to sleep) fails to reload properly and I have to tell windows to discard the hibernated state in order to get it to successfully boot.