I had to buy case-fans for my current computer, which I built back in August 2020. I have had issues with the fans rotating askew and making an unpleasant noise. I had already replaced two before one of my replacement fans started to go. In February, I fixed the replacement fan by punching the top of my computer case. Unfortunately, the punch solution became unreliable on the morning of October 26, 2024. Having work to do, I unplugged the offending fan. I think I can harvest case fans from my previous desktop PC, which I built in 2011.