What does "PowerSave Mode" actually do?

[DeanGibson Distinguished Bibliophile]

The manual says, "Your NOOK features a PowerSave Mode that fine-tunes your NOOK's performance to save power and extend its battery charge."

I initially thought that "PowerSave Mode" (in addition having a reduced screen brightness) might have other noticeable performance effects, despite the (typical) B&N ambiguous and vague statement above.  However, in a rendering test I just did, I see no performance change between having the mode on or off.

OK, so perhaps the mode saves the brightness setting?  Nope;  if you set the mode on, increase the brightness setting, set the mode off and then on again, it doesn't remember your previous brightness setting.  If all it does is reduce the brightness setting to a fixed value, what good is that?  It's much easier to just adjust the brightness manually.

Oh well, at least it feels good to save power.

[Reisnice]

I wondered about that too, given the vague explanation. I never saw that it did much, except that I seem to remember that it shut down my web connection quickly, when I would leave the Rhapsody website (not the app) playing for background music. So now, I manually turn it off, change the screen timeout to 1 hour, and turn the brightness all the way down, if I'm going to leave it playing. (And, Yes, I'm too cheap to get another charger nearer my sound system and too lazy to move my regular one out of the bedroom... ) Now, I'm going to have to experiment to see why I decided to do that when I first got it in November. Maybe it was just my imagination. It would be nice if BN could have one of their developers on here from time to time who might be able to answer technical questions lilke that, for those of us who wonder about such things.

[roustabout]

reisnice, I think you've pinned down another thing that powersave does, aside from dimming the screen - it puts your network connection in a lower power mode, and it sounds like it also shuts the adapter down as soon as the screen goes dark. It could be that that's really all it does as far as networking - be sure that you're not polling wifi when the device isn't in use - but my memory on this is that for some folks, that low-power mode on the wifi is a real headache. When the NT was first released, I'm pretty sure I read reports from folks who were suggesting that an early network troubleshooting step was to be sure you weren't in power saving mode. 

BN's history with modifying the Nook network stack is not a catalog of their finest efforts... 

[triggerjerk]

     You do realize, don't you, that any micro usb cable will charge your Nook tablet, right?

When plugged into the original cable the device says "charging". When unplugged it says "discharging". When plugged into any other cable it says "not charging", which is a downright lie; it charges just fine and you can download files fron your computer, if that is where you have the cable attached.

     Replacement NT cables run +/- $25.00. Micro usb cables are available on eBay for less than a dollar. I wonder if that has anthing to do with it?

[bobstro]

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triggerjerk wrote:

     You do realize, don't you, that any micro usb cable will charge your Nook tablet, right?

When plugged into the original cable the device says "charging". When unplugged it says "discharging". When plugged into any other cable it says "not charging", which is a downright lie; it charges just fine and you can download files fron your computer, if that is where you have the cable attached.

     Replacement NT cables run +/- $25.00. Micro usb cables are available on eBay for less than a dollar. I wonder if that has anthing to do with it?

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It can charge with any microUSB cable, but there will be a significant difference in how quickly it will charge. For a casual user, this may be no big deal. For someone who runs their battery down below 50% daily, it might be a problem. A low power charger might also not charge with the screen on or the unit in use.

The B&N charger is 2A, and the cable is proprietary with extra pins to support the quick charge. If I regularly top off overnight with the screen and wifi off before the unit gets low, a 1A charger seems to work well enough with a standard microUSB cable.

[bobstro]

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roustabout wrote:

reisnice, I think you've pinned down another thing that powersave does, aside from dimming the screen - it puts your network connection in a lower power mode, and it sounds like it also shuts the adapter down as soon as the screen goes dark.

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I actually read somewhere that this is how it works, but darned if I can remember where I read it! Does it set screen power off to 2 min when not in use as well?