Congrats on your quiet computer! I think when Lord Jim opened the case and started moving stuff around to insert memory/CD burner, he prolly moved a wire that was brushing against the fan. That’s why it wasn’t making the noise when he put it back together.
Hate to spoil the magic, as I’m sure Lord Jim is a fine person.
Enjoy the silence!
Joseph, our hardware guy at work, can do the same. He can lay his hands on your grungy old 486 (the one with so much dust inside that it smokes if you leave it on too long), and it immediately becomes a Pentium. Sometimes he throws his head back and starts to shake: “I feel the POWER!!!”, and that 486 turns into a fully-loaded P4. He’s quick, too. One of our faculty swears he turned away to answer the phone, and by the time he hung up there was an upgraded PC on his desk. All he saw was a shadow disappearing down the hall…