The PSU in an old server box died this weekend, the way they usually do: fans spin for a second, then nothing, then a faint smell that tells you exactly what's happened before you've even got the lid off. Bulging capacitors. Two of them on the secondary side, domed tops, a little crust of electrolyte where there shouldn't be any.
The sensible thing is to bin it. A new unit is forty-odd quid and an hour you'll never get back. But these were standard parts, 1000µF 16V, the sort that the capacitor plague of the mid-2000s made everyone learn the markings of, and I had a strip of decent low-ESR ones in a drawer. So I discharged the big primary cap first, which you absolutely must do unless you enjoy surprises, desoldered the two offenders, and dropped the replacements in watching polarity like a hawk.
Powered it up on a bench load before trusting it near anything I cared about. Rails were steady, ripple looked sane on the scope, no smell. It's back in the box and the server's been up since Saturday.
I know the maths doesn't really work. My time is worth more than forty pounds and I'd not bill myself out at the rate that repair "saved." But that's not the point. The point is that the thing was fixable, the fix was two parts and a steady hand, and binning a working power supply for the want of twenty pence of capacitor offends me on a level I can't quite argue my way out of. Some repairs are economic. This one was just satisfying.