Check your USB devices - they can wake up your PC. You can disable this on a per-device level in the device manager. Find the device, open it's properties and f

Check your USB devices - they can wake up your PC. You can disable this on a per-device level in the device manager. Find the device, open it's properties and find the setting under the "Power management" tab. A windows PC can also be woken up by "Wake-on-LAN" magic packets sent to your network card. Go to your network adapters and open it's properties. Press the 'Configure' button. Go to the Advanced tab and find "Wake on Magic Packet" and turn it off.