alt Hacker NewsI had the same inclination back in the 90s when I upgraded my Cyrix 486 SLC2 50MHz without a heat sink (which seems like a no-no in retrospect) to Cyrix MediaGX 133MHz. The stocker fan was immediately noticeable. I thought I had done something wrong.
Upgrading and Repairing PCs 4th edition even says directly, that some shady resellers will put a heatsink on a chip that they're running beyond spec, but that Intel designs all their processors to run at rated speed without one.