Computer hibernating at strange times

[BarnabasSackett]

Win 7 x64 SP1. ASUS A8N5X motherboard with an Athalon 64 X2 processor.

I have my hibernation timer set to 45 minutes of inactivity or if my UPS battery level drops below 50%.

For the past week or so, I'll leave my computer to get a snack or something and when I come back it has started hibernating. I restart the computer and it tells me that it shut down because battery levels are low.

There are no power glitches. No alarms from the UPS and the battery monitor shows that the battery is charged.

One thing did just occur to me. This all started after we had a major thunderstorm with a power failure which prompted an automatic shutdown. Is there a flag that didn't get reset?

Thoughts?

Thanks.

 

[BarnabasSackett]

Still happening. Went to the kitchen to get a cup of coffee and when I came back, the computer was off.

 

[UsernameIssues]

Set the inactivity time to 1 minute and watch it go into hibernation...

Then wake it up and set it back to 45 minutes.

 

[BarnabasSackett]

I'm thinking that the problem has something to do with my UPS. I unplugged the UPS's USB cable and the problem vanished.

 

[UsernameIssues]

Are you using W7 to watch the UPS levels or a 3rd party app?

 

[BarnabasSackett]

I'm letting Win 7 do it.

 

[UsernameIssues]

Does W7 report that the battery is at 100%?

What is the manuf/model of the UPS?

 

[BarnabasSackett]

Does W7 report that the battery is at 100%?

What is the manuf/model of the UPS?

Yep, 100%. APC Smart-UPS Pro 500.

 

[UsernameIssues]

That particular APC model is not meant for use with a Power Factor Corrected (PFC) computer supply.

See this PDF.

 

[BarnabasSackett]

Oh wow. This is really getting complicated.

In words of one syllable, why would that cause my computer to hibernate?

 

[UsernameIssues]

In one office that I was helping out in, there were several APC UPS units - none were designed for PFC supplies. They too had a power outage due to a storm - after that, they had two computers that kept going into hibernation at random times. APC walked me thru some tests and determined that the UPS units were fine (I have my doubts), but they suggested not putting them on these types of PSUs.

That office has not purchased the more expensive UPS & I ended up removing the UPS units from those two computers. Neither computer had this hibernation problem before that one storm/outage. If it were up to me, I would replace the PSU in one of them just to see what that does.

All of the computers in that office use XP and the APC Powerchute app. If you will notice, I only have W7 inside a VM. I don't use W7 for day to day computing - so I don't know what kind of detail to expect in the W7 logs for this type of APC UPS. The APC Powerchute app sometimes mentioned noise on the line before putting these two computers into hibernation. I don't know if the Powerchute app traps more events than W7 does.

You mentioned coming back from getting coffee and finding the computer going into hibernation. Did you nuke your coffee in the microwave? Or do anything that could disturb the power?

Two free things that you can try:
1) Sit back and watch the computer for the length of time that you were away getting coffee - see if the computer hibernates when nothing else changes.
2) Install Powerchute and see if it gives more details.