My old PSU, a Seasonic Prime Titanium, started going wonky a few months ago, suddenly shutting off while gaming, as if one of the protections was being triggered. Since it was only 7 years old, not that old for a PSU, I wanted to take it apart and see if I could work out what went wrong. It has been setting on my bench since then, but this weekend I finally got around to dismantling it.
The most odd thing I found was an X2 capacitor - part of the filtering on the high-voltage side - which measured very low. It's marked 470nF±10%, but was only 390nF. This sort of capacitor is normally very reliable, so it should have still been in-spec. I pried the outer casing off to take a look, and found this:
As per the markings on the fragment of casing visible in the photo, this is a Carli MPX X2 capacitor. The inside of an X2 capacitor is supposed to be a roll of plastic film with a thin layer of metal deposited evenly on the surface. I know that small holes can build up over time, as the capacitor "self-heals" after voltage spikes, but that would be small holes, not massive areas of metal missing like in the photo.
Was it manufactured like this, or has it degraded over time? Has anyone else seen this sort of failure? I don't think this was the reason the PSU failed, but it's still not good.
The most odd thing I found was an X2 capacitor - part of the filtering on the high-voltage side - which measured very low. It's marked 470nF±10%, but was only 390nF. This sort of capacitor is normally very reliable, so it should have still been in-spec. I pried the outer casing off to take a look, and found this:
As per the markings on the fragment of casing visible in the photo, this is a Carli MPX X2 capacitor. The inside of an X2 capacitor is supposed to be a roll of plastic film with a thin layer of metal deposited evenly on the surface. I know that small holes can build up over time, as the capacitor "self-heals" after voltage spikes, but that would be small holes, not massive areas of metal missing like in the photo.
Was it manufactured like this, or has it degraded over time? Has anyone else seen this sort of failure? I don't think this was the reason the PSU failed, but it's still not good.