It's been a while since anything major was posted here, hasn't it
I just opened up a 2002-vintage FSP (rebranded AOpen) ATX-250GT to add to my capacitor lists (currently private but can upload if requested).
While several of the output capacitors were bad as expected (already the case when I got it years ago), the few survivors still measured surprisingly low in ESR despite being Teapo SEK series (GP according to the datasheet): A 2200µF 10V (10mm diameter by 20mm tall) measured 0.04Ω, and a 3300µF version (30mm tall) even read "0.00Ω" on the Atlas ESR+. (Of course I still didn't trust them to re-use or even justify keeping, between being Teapo and their capacitance measuring over-tolerance presumably from the oxide layer thinning out)
So I wonder if Taiwanese (or Chinese) capacitor manufacturers provide the option for bulk customers to specify a different series label than what's really in the capacitors? (Possibly used in an attempt on the PSU maker's part to foil hardware clones? But also well-meaning repairers at the same time )
I still stand by it being utterly reckless to use truly general-purpose capacitors (which Japanese GP series probably are) in place of low-ESR, of course.
But I guess this theory also explains some confusing experiences of certain BadCaps.net members (such as momaka - who to be fair is one of their nicer guys)…
EDIT: Or I suppose there's the more mundane possibility of simply specifying lower ESR than standard for the series.