My computers turn off completely instead of going to the screensaver

I'm not sure what I did but my computer (Vista) has started acting differently in a bad way.

I had it set for almost a year now that if I had something minimized (e.g., Internet Explorer) and there was no activity for 10 minutes, it would go to a blank screensaver.

Now all of a sudden today, if I'm away 10 minutes it just turns off completely. Then I have to press the button to turn in on and sign in and reopen whatever I was working on.

This is really bad, because sometimes I am doing things where I cannot afford to lose my connection.

I've checked the battery, it is at 100%, and I never use it on battery, I always keep it plugged in. I checked the connection from the power outlet to the middle block with the light to my computer, and everything is lit up and connected.

I noticed Power Settings for the first time today, and it is on VAIO Optimized (but I am fairly certain I didn't mess around with that at all.)

 

did u get a update that could have caused this problem? u may have alreddy dune this but did u check your screen saver settings???

 

As earl stated it might be an update...
I think something changed your power setting whther it be in the bios or Vista itself.. Couldn't be the battery unless it's really old.. (mean like 6 years or better)... So I would start with the screen saver settings and then check power setting in Vista then check your bios setting for power time...