I've had the first unpleasant experience with my Fullnut HP-41CV yesterday. During a business trip I got it out of its pouch for some quick calculations only to discover that it had turned completely nuts over night.
It did not turn on correct, displayed only garbage, etc. All quick recovery actions failed. When I got home I was able to reset it by taking out the batteries, shorting the contacts for half an hour (combined with pressing the On-key for two minutes), then pressing Backspace-Enter-On a couple of times. That when I was able to turn it on as normal again, and after performing a master clear (Backspace-On) the episode was over.
However, when I had my programs wanded in again I had the impression, that the calculator is now a good bit faster than before. Is that only in my imagination or can this really be true?
Maybe discharging all the capacitances in the system cleared some memory garbage or else??
And BTW, how can such a crash happen in the first place? I mean, I didn't even touch the unit before it went nuts...