Last time I have seen data damage was about 2005, this was multiple SATA drives connected to a regular consumer motherboard running Linux (sorry, don't remember the brands). If I remember right, I think there was an 8-byte block damaged every few gigabyte transferred or so? So a very high number of damaged files given I had a few terabytes of data.

I never found the cause, because I just switched to a completely different system to copy data. I know it was not disk-specific because this was happening on multiple hard drives, nor it was physical damage, as SMART/syslog were silent, and reading the disk again was giving correct data. Memory was fine -- not ECC, but I did run a lot of memtest's on it.

Later on, I found some blog posts which mentioned the similar problem and claim it was result of bad SATA card, or bad cable, or even bad power supply. I remember there was original one made by Jeff Bonwick on his ZFS blog, but I cannot find it anymore. Here is a more modern link instead: https://changelog.complete.org/archives/9769-silent-data-cor...

I now have the homegrown checksumming solution which I use after each major file transfer, and I have not seen any data corruption yet (*known on the wood().