Most GPUs will have fan spin & lights if only on pcie power (the pcie slot provides 75W without external connection), but then misbehave during display; I know it sounds stupid but make sure the 12V power connector on the top of the card is firmly plugged in, that connector in particular has a reputation for being unreliable.

Apparently the tested interface that wasn’t suitable was CAMM2.

Hopefully either the interface or the manufacturing process improves so that future products can use CAMM2 for this kind of bandwidth.

I wish.

It was a bcachefs array with data replicas being a mix of 1,2 & 4 depending on what was most important, but thankfully I had the foresight to set metadata to be mirrored for all 4 drives.

I didn’t get the good fortune of only having to do a resilver, but all I really had to do was fsck to remove references to non-existent nodes until the system would mount read-only, then back it up and rebuild it.

NixOS did save my bacon re: being able to get back to work on the same system by morning.

A few months ago I accidentally dd’d ~3GiB to the beginning of one of the drives in a 4 drive array… That was fun to rebuild.