PROBLEM COMES FROM CPU WILD OVERCLOCK
please read below exactly ....100% this way will solve your problem
Afraid not. Turning it on today it had dropped 5% while off claiming file manager running in the background, and after 45 minutes of browsing the web I lost another 16%. So call it 20% an hour, for a total of 5 hours... of BROWSING.
That's with battery saver on and brightness at 20%.
I bought this to for its battery life, and it is NOWHERE NEAR what microsoft promised.