I did find an old K6-2 system with no TIM-paste on the heatsync once, but that's the only machine I've ever seen (that needed a heatsync) without it, and it actually turned out the reason it had been decommissioned was because it overheated.
OS: Windows 10 64 bit Professional
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56
CPU: AMD Ryzen 5900X
RAM: 16GB
GPU: Radeon Vega 56
