I had the annoying problem of putting my computer on standby mode for the night, only to have it mysteriously come back on due to some device activity that I didn’t know about!
Here’s how I investigated the issue and found a fix:
1. I opened a command window with start > run > cmd
2. I typed in powercfg /devicequery wake_armed
This brought up a list of devices capable of waking my computer from standby.
I found the culprit almost immediately: the network card. (NVIDIA Nforce Networking Controller)
3. I typed in powercfg /devicedisablewake “NVIDIA Nforce Networking Controller)”
4. Problem solved.
Apparently, there’s an alternate way of shutting off this “capability,” using control panel > system > hardware > device manager > network adapters and then bringing up the properties > power management option of the network controller. There’s also a way to enable devices, with the command /deviceenablewake. (Typing in /? Will bring up a help file with the interface syntax that’s needed.)
Just for safety, I disablewaked all the other devices on the list except the keyboard and mouse. One would think there’s a single place in the control panel to find all these wake_armed devices (and even better, if it was in the Power Options), but there isn’t.