ECC RAM won't save your modded Minecraft world.

Probably not. World corruption from 100 mods is almost never a memory error issue.

ECC RAM is for catching rare bit flips — cosmic ray stuff. That’s not what corrupts your world. The usual suspects: mod conflicts, crash during save, chunk errors from bad interactions, disk write failures, or just forgetting to shut down cleanly. ECC won’t help with any of that.

If you’re running a dedicated server, you’re better off spending that money on a solid backup script and a UPS. Back up your world folder every hour. That’s what actually prevents lost progress.

Invest in backups, not ECC.