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English Forums => Hardware and Performance => Topic started by: foxxx0 on March 13, 2026, 10:15:11 AM

Title: DEC750 NVMe thermal pad?
Post by: foxxx0 on March 13, 2026, 10:15:11 AM
Hey folks,

I recently received my DEC750 and noticed the NVMe temperature is a bit high for my taste.

Depending on the room/ambient temperature and the I/O load, the NVMe sits around 63-67°C in idle and easily goes up to 75°C+ under load.

The CPU on the other hand stays comparatively cool, sitting around 48-52°C at idle, with an enclosure surface temperature of ~39°C.

I wasn't able to find teardown pictures of the DEC750, only the DEC850 on reddit, which is based on a completely different PCB and enclosure. However, there it looked like the NVMe had no "direct" thermal contact with the enclosure. Apparently there is a recess milled into the enclosure top to make space for the NVMe but I didn't see any thermal pads there.

Comparing the NVMe temperature and the enclosure surface temperature leads me to believe that there is no direct thermal transfer between the two, only passive thermal radiation.

So before I open the DEC750 myself, I thought I'd just post this question here.
I'm kinda hoping I could just purchase a thermal pad of the necessary thickness (guessing somewhere between 0.5-3mm) to improve the NVMe temperature.


Thanks in advance!


Cheers,
foxxx0
Title: Re: DEC750 NVMe thermal pad?
Post by: pfry on March 13, 2026, 02:27:44 PM
Quote from: foxxx0 on Today at 10:15:11 AM[...]I'm kinda hoping I could just purchase a thermal pad of the necessary thickness (guessing somewhere between 0.5-3mm) to improve the NVMe temperature.[...]

Some things to consider:

You'll want a dead soft pad. I'd recommend getting a few and seeing what you can work with. Ideally you can trial the thing (such that you can directly view contact) or take an impression (via, say, very soft clay) to try to see how applying pressure to the controller will flex the board. Some motherboards use medium foam supports under the board, but sourcing something like that might be tough. On one of my tiny ARMs I had to trial several pads and thicknesses to find one that didn't simply flex the board such that the controller surface was no longer parallel to the opposite surface, resulting in limited contact. Foam pads are garbage from a thermal standpoint, but may be better from a physical standpoint.

Good luck.