Sun Aug 31, 2014 12:13 pm
probably the most important B+ "power problem" improvement has been the doubling of the polyfuse trip level, meaning less prop in the fuse itself, and less instances of an (almost) tripped fuse.
after that, the main change that can help reliability is the new built in brownout detector, its not perfect as it will not detect everything, (only drops below 4.65V are detected), but its a huge improvement over not having any power integrity checking at all! Not only will it turn off the PWR LED, but short intervals will also be caught, and will be shown as a small "rainbow square" in the GUI screen.
B+ now also no longer suffers from USB plugin power dropping issues (non hot plug-ability) that could corrupt cards when a USB device was plugged in "hot" due to 5V sagging causing memory corruptions.
p.s. yes, stability is mainly an issue of first-most power, second-most power and then using a good quality sd-card, with a reliable internal controller (fake cards are the worst in this regards), and lastly frequent updates to get rid of bugs, and stability issues. Recent firmware is much better than older one in this regards, especially when it comes to USB and SD-card driver improvements.