Computer unexpectedly going into standby

[GRoston]

My computer (Win 7 x64 Pro, fully patched) has recently started exhibiting a highly undesirable behavior: Three times over the past several days, the computer went into standby mode (I presume S3 state) without my commanding it to do so and without the specified time (Power Settings) having elapsed. Tonight, for example, I was editing a MS Word document while speaking to a colleague on my softphone. I stopped editing for about 30 seconds and the computer went into standby. What was truly peculiar is that when I restarted the computer (which I did quickly), the softphone connection was still active. Any suggestions for trying to track down the cause? I looked in the event log and found nothing useful. Powercfg does not seem to report what put the computer to sleep (only what wakes it). The computer has not been rebooted for seven days, but I would certainly hope that this is not the cause.

 

[whs]

Check your power settings. For some odd reason they sometimes set themselves without intervention. I have that problem too - at times. Just this afternoon my screen shut off. The setting was '20 min' although I always set it to 'never'. I have not yet found the source of the problem.

 

[GRoston]

whs - thanks for the reply. I just checked and both screen and standby are set to 20 minutes as expected.