Yes; the internal battery may not be fully charged when you receive a new unit. Its charge may have fully drained sitting in the warehouse.
Operation on battery timing is directly related to your usage and can vary vastly depending on what programs you're running. Obviously gaming, videos, downloading YouTube stuff, etc put a far greater load on the battery than just web surfing or writing a text document. My 17R SE 7720 varies from around 2½ hours up to 6 hours on idle.
Again, charging time is totally dependent on how far discharged the battery is. Time-wise it could vary from 10 or 20 minutes to a couple of hours.
All DELL laptops should be running ideally (where there's a mains source) with the adaptor plugged in. For most practical purposes—under this scenario—there's absolutely no difference between chargers of different outputs. Their output is measured in volts and amps and not watts. You should only use the charger that came with the laptop, as its matched to the machine by DELL for optimal performance.
Click Start > Control Panel > System and Security > Power Options
Under your power settings options, you should adjust for the best battery v, mains options depending on your personal usage. The best setting (in my opinion, "balanced") optimises the battery and the mains power automatically, and leaves the battery nearly fully charged should you unplug the charger and start using battery only. Doing this also "conditions" the battery better for longevity, as it's never fully drained and/or fully charged for lengthy periods.
The wattage required to power an average laptop, with everything running including its fan and HDD and display is around 200W to 250W.
"Sleep" mode uses around 5W of power, and "Hibernate" uses less than 1W.
ausGeoff
58 Posts
0
February 5th, 2013 18:00
—Hope this helps. :emotion-1: