Though I might not be about to overhaul my PC setup, I did wind up ordering an external drive enclosure, and it arrived today. Unfortunately it’s not quite working out as well as I’d hoped; it was a tight squeeze getting the drive in, and one of the plugs that had to be undone to remove the drive tray was quite stubborn.
But the disappointing part is that the chipset this enclosure uses doesn’t appear to support the SMART commands. I have three drives left over from the previous Linux box, but I know one of them was going bad, and without the SMART status I can’t tell which one it was. I tried booting up the old box since I still had it lying around, but it shuts off a couple seconds after turning it on. It might be a power supply short, or a motherboard problem, but I’m not going to waste my time troubleshooting an ancient Pentium II system.
Oh well, it was a cheap enclosure and it’ll still serve its purpose as a somewhat more portable drive for data and backups, including the PS3 now.