> Wow I came back to post this exact reply. I set my system to a slightly high frequency, ran memtest overnight with errors.
>
> Set it back down to a supported frequency, ran a full memtest suite again with no errors.
Cool. You tested your memory at some point in the past.
How do you know it's still working properly and hasn't flipped any bits?
You don't. Because you have no practical way of testing the integrity of the data without running an intrusive tool like memtest86 that basically monopolizes the use of the computer.
Being able to detect these types of memory errors at a hardware level while the processor is doing other things is the fundamental capability that ECC gives you that you otherwise wouldn't have, no matter how thoroughly you run memtest86.
You likely wouldn't know if you had random bit flips. It'd manifest as silent data corruption. You might be okay with that. Others aren't.
It's not a matter of overclocking. Bit flips are a fact of life running with 32+ GB RAM. Leaving your machine on 24/7 (even if in sleep) stacks the odds against you.
Obviously this is just anecdote but I have a work laptop with 128GB of non-ECC ram , use all of it every day and never noticed any issues. I'm not saying there aren't any, but it just....works.
Set it back down to a supported frequency, ran a full memtest suite again with no errors.
Never had any issues since.