My K660i keeps turning itself off and doesnt turn on again for long periods of time . taking the batery out and back in again does not change the situation, you cant do anything with it for about 15-20 minutes, after which you can then turn the phone back on again... it does this 3 or 4 times an hour, and its annoying!!!!

as i do not know what laptop we are talking about here i asume its not a notebook
if it is the time is slightly lower (6-8 hours)
a normal lap top 10 - 12 hours.
some super batery laptops come with an own (long) guide how to keep the batery alive.

to keep the batery alive a long period of time charge it from 50% not when its at critical.

If u can take out the batery when you are using cable and its fully charged it also has a longer life time. or just take out the cable when its at 100% and recharge it when it gets to 50%

dont have your computer in the lap it can over heat the computer/batery and the lifte time gets even lower.

http://www.lg.com/hk_en/support/product-help/CT20136018-1434699326488-power-on-off

If you've changed it's location or added speakers, or placed anything on top of it since the problem started then consider that it may just be over heating.

Easy way to check. Crank the vehicle while running remove one of the battery cables from the battery if the ingine dies your alternator is bad. I'll bet it is the alternator.

Best Way reset the set,U right it well reboot itself,before u go to sleep unplug the tv,take out the bateries to remote.Morning,plug in and put the bateris back might reset it self.

Set setting to AUTO.
Charge batery or change batery.
Diract it to a lighted spot use external light.
set mode to power save and extend time to longer period.
Vitally

firmware(Operating system) is damaged . you need to reinstall it .
This could occur due to many reasons like virus attack ,sudden removal of the battery while the phone is on,sudden switch off the cell due to low battery etc ..

if you firmware backup you can reinstall it with your normal datacable by using the PC suite or you can contact the technician

Regards
-Dileep

Visit this site for simple trouble shooting steps of Blackberry

return it...

Its the BULB people! You need to change it every 3 to 5 years! I have had my sony 55" for 6 years... I had Best Buy come out 3 years ago, changed the bulb... it worked fine. Just started flasshing and shut its self off and back on again. Time for another bulb.