Just bought a UX31E, battery life is suddenly bad

I recently bought an ASUS UX31E from eBay and received it yesterday.
The OS had heaps of bloatware so I decided to just format it and install my own copy. I did that, installed the appropriate drivers, and set it to charge.
It got time to charge to 100% and I used it in bed for about an hour, which drained about 20% of the battery. During the time that I was using it, it reported to have 5 to 6 hours remaining.
Before I went to sleep, I downloaded and installed all the Windows updates that it wanted, and went to bed.
This morning, I used it for about 10 minutes and the battery had drained to 91%. It reported as having close to 3 hours remaining.

Anyone know what might be the issue?

 

Energy management software could be the issue, just a thought. Some other tweaks too.

I would have left the factory installation and just removed individual programs that you don't need ( it's probably faster too than re-installing ).

 

I was certainly thinking that, but the fact that it was lasting really nicely last night made me think otherwise.

I wouldn't think that the included software would more than double the battery life, anyway.

 

No, the software itself wouldn't make a drastic change, but your power settings will. The approximate spitball of hours remaining is just that; a guesstimate. It's also based off of your load/demand placed on the battery.

Generally, you should get closer to the former projected estimate.