Rock 5B+ NVMe SSD overheating

#1

On a Rock 5B+ SBC, I have observed the following:

I have a 1TB Samsung Evo Plus NVMe SSD. When I insert this SSD directly into either of the SBC’s NVMe ports, it continuously heats up over time. After 10 minutes, it reaches 45°C, and later, it climbs up to 60°C, even though I am not doing anything with it, it is completely idle (not even mounted).

SMART data after 10 minutes:

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I bought an NVMe extension cable from AliExpress (link). Under the same conditions, when I connect the same SSD via this extension cable, it does not heat up. After 10 minutes, the temperature is only 30°C and remains stable.

SMART data after 10 minutes using the extension cable:

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image.png1425×1159 38.2 KB

Of course, the data is accurate when checked manually, the temperature difference is significantly noticeable.

Can anyone explain this phenomenon?

#2

ASPM is not enabled on these arm boards so drives are on all the time. The drive with the extension is just farther from the board which is heating it up when inserted directly.