When I powered mine up after being unplugged for several years (with brand new batteries), I immediately heard a hiss and then the magic smoke came out. The magic smoke came from my Viper22a chip, which completely obliterated the markings, and I didn't even know what it was til I got here :-) Both of my 200V caps are swollen. All the other caps look ok. In short, I think there are probably multiple failure modes for this part, especially depending which caps died.

I just placed my Digi-Key order, and will update when I get the parts installed....

Hi, occasional hardware hacker here. I have a few piles of old electronics that I've been meaning to see if I can bring back to life, so I might be posting about those as I find time, but mostly I want to contribute to a thread about repairing a UPS that I just found.