Originally Posted by Dave W
2. Reader time vs. page turns. This one is really puzzling. According to what I've read about the e-ink displays, power is only used when a page is being turned. Therefore, I should be able to leave my reader on indefinitely up to the self-discharge limit. However, I recognize that the reader must have a microprocessor that needs power whenever the unit is on. So why the claim (not by Sony) that power is only used when a page is turned? Maybe the display only uses power then, but that isn't the real world. Since the microprocessor must use power, Sony should specify both page turn and run time limits for those of us who don't go through 7500 pages within the run time limit.
The screen, eInk, requires power only when the page refreshes (turn, access menu, etc.)
Whether a reader continues to consume power when you hit power button or not is up to this particular reader design.
For example iRex iLiad doesn't. So, it takes freaking (pardon my french) 40-45 seconds to turn it on each time you want to read a book.
In the case of Sony Reader, when you "turn off" the power, it actually only clears the screen and make all buttons stop responding to anything. You can call it "hold" button, instead of power button. Because essencialy you put your reader on a "hold", like you can do with mp3 player when you turn it on and press hold button, so when you put it into your bag "hold" state prevents any accidental button pushes.
Starting with the latest firmware of PRS-505, you have an option of a full shutdown of the reader via menu. In this way, you can really turn off your reader between reading sessions. Although, you must be aware that it will take probably 1 minute to start it up and probably it consumes more power than usual when powering up.
So, here you go. You do have a choice. I, personally, never ever shut down my reader. I would not buy ebook reader that didn't have this "hold" state. I love the idea that whenever I want to read a book I just push power button and the book appears within a second. I don't know about 300, but I can give you some examples about 500 and 505.
(We are talking about page turns only, anything else, such as accessing TOC, jumping many pages ahead, accessing menu, bookmarks etc., I believe consume more power than a mere page turn)
500 out of box could hold charge for 3 weeks if I read 30 pages/day
505 out of box could hold charge for 2 weeks if I read 60-70 pages/day (I started to use ebook reader a lot more 5-6 months after I bought 500. Usually I could read a book only in the evening, in bed before I go to sleep, later I started to take 500, then 505 to work and read a book during lunch time).
[EDIT] one small addition. We are talking about reading book on internal memory. No memory cards. Memory cards consume more power. Maybe, as much as x1.5 more? I am not sure.