My computer build now includes a piece of structural 8.5x11 printer paper.
I tracked the tapping noise to the case fan, poked at it a bit, and realized it got perfectly happy with just a bit of upward support. So, a bit of bridging between that and the top of the card cutouts just below, and I have a near-silent computer again! (Ignore the dust, that's the next task.) #lowtechtech
Can I humbly sugest to exchange the screws of the fan for a new set and perhaps add a little O-ring to it, to absorb extra vibration?
Because that is a hack (and a fine one, as it seems to fix the issue) but it is not a solution!
I'm from the country that makes a lifestyle of hacking a quick fix for anything instead of actually solving an issue, as more often than not a definitive solution for a problem is either too expensive, complex or requires climbing up a bureaucratic ladder for an approval.
Staring me down into shame does not work with me.
It's just dem dare city folks that obviously didn't stonk up on duck tape when had der chance.