Post-upgrade notes: the system drive had exhibited massive read errors, coincidentally after the storage upgrade... and no, it was not the IDE cable.

I had to mirror the drive to another one. That was around September 1, 2023. Though interestingly, I had to position the IDE cable at the right position, otherwise the data transfer speed would literally be in the kilobyte range.

Old drive: Hitachi 180GXP IC35L060AVV207 - 61.4GB
Current drive: Western Digital Caviar WD800BB-22JHC0 - 80GB

That particular Western Digital was one of the many eBay purchases that sat mostly in storage until it was used in a Windows XP build, but even then, it wasn't used often. Found some unique data on that drive and sent that to the NAS before using it as a replacement system drive. It also had nearly 20K hours on it and no bad or pending sectors when initially examined.