For long term applications I much prefer passive cooling (AKA a hunk of metal.) I have one Raspberry Pi 4B in a case with a small heat sink on the processor and

For long term applications I much prefer passive cooling (AKA a hunk of metal.) I have one Raspberry Pi 4B in a case with a small heat sink on the processor and a small fan driven from the GPIO pins. It keeps the processor within limits even when overclocked and heavily loaded. Some day the fan will stop working and the processor will overheat (under heavy load) and throttle to prevent self destruction. I have two Compute Modules (CM4s) and found a passive heat sink that is finned aluminum that covers the entire module. There is no fan to fail. I can overclock the CM4 to 2 GHz and load it for stress testing and it remains well within limits. One of these is equipped with an NVME SSD and I was surprised to see it reach excessive temperatures under heavy loads despite the PCIe x1 connection on the Pi. I got a "hunk of copper" NVME cooler, cut it to fit a 2230 NVME and it keeps the NVME SSD within reasonable limits.