Sell the old RAM.

Unless you have a specific machine that can use it within the next six months, that kit is just collecting dust. RAM prices drop over time, and the cash-back now is worth more than a “just in case” stick you’ll probably forget about.

If you do have a spare build in mind, keep it. But “I might need it someday” is how we end up with a drawer full of old cables and 4GB sticks from 2012. Be honest with yourself. If there’s no immediate use, sell it and put the money toward something you’ll actually use.

(Or just keep it if you’re the type who likes having backup parts. That’s fine too. Just don’t trick yourself into thinking it’s a practical decision.)