So, back in 2014 I had the following issues with my Dell Inspiron 5520:
As you can tell from the thread, it ended up being the power board. Fast forward to a few months ago, with very reliable use and I started having the shutdown problems once again. Having seen this movie before, I ordered a new power button board. Replaced it, and no love... still the same problems. Chalked it up to possibly getting a lemon out of the box (having to order what are likely cannibalized parts off of eBay), so I ordered another one. This time, along with the charging port and wiring just to be sure there was not a short in the wire. Still... Having the same issues. Once again, I do not believe this to be a battery issue because the symptoms can appear when the machine is without a battery, on battery with no AC adapter, battery and AC adapter plugged in, etc.
Are there any other things that could possibly cause a random power-off besides what I've already replaced or eliminated? For example, could there be an issue with the power going to the LCD display, causing a short or other electrical fault that makes the system shut off? Perhaps the same thing with the keyboard?
I really would love to fix this problem once and for all, as my family is adding another baby soon so a new laptop is not in the family budget!