No idea where this is going but it started with me buying a dirt cheap External USB NVMe HD and a 1Tb WD 770 Black to go in it. This generated some discussion in the 'what did you buy today thread' about in particular heat issues and external HDD's and now Solid State HD's.
So just some basic experimental data using
'Crystal Disk Mark' to generate some consistent loads and
CPUID's Hardware monitor to keep an eye on the internal Temperatures of the drives under load.
Same basic tests (so far) 5x 1Gb test data using long read writes down to shorter more choppy reads and writes typically not what you would be using an external drive for.
The old 3 1/2" Seagate is a relic and I have since donated it to a mate of mine, no temp data was available from it but I have never felt it get even warm during multi hundred Gb backups in the past.
The 2 1/2" WD is part of my NAS disaster recovery pack if it is ever needed. Typically it gets plugged in and I go to bed while the NAS does it's thing. Slow speed isn't an issue and unless you were running it in an Aussie Summer on short read writes then Temps are unlikely to ever be an issue. To this end I can't see any point doing further testing but feel free to test your own spinny ones and add the data.
Now where it gets really interesting
Below is just a first round of testing based on a stock trash enclosure where the NVMe has no contact with it other than air. I do have some 1mm thermal pads so that is round two to see if there is a simple temperature drop for the sake of a few cents extra. I also have a few NVMe heatsinks and a better enclosure coming for some additional testing next week.
Fairly logical as the data transfer rate increases so does the Temperature.
EDIT Added USB 3.2 Gen 1 port test from another PC.
NVMe drives and in particular as USB 4 when it gets released with some of the PCIe4 grade drives used. What and how in the hell will you be keeping them cool or will they even need to be?