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English Forums => Hardware and Performance => Topic started by: vlorentz on February 13, 2022, 11:50:47 am

Title: Deciso DEC690: thermal design
Post by: vlorentz on February 13, 2022, 11:50:47 am
Hello,

I have upgraded my DEC690 from 8GB DDR3L to 16GB DDR3L with ECC, and added a second SSD of 1TB to the original 256GB SSD. After reassembling, I encounter cooling issues with the CPU. The design of the thermal contact between the CPU and the heat-sink does not provide a natural mechanical contact pressure, so that thermal paste or even thermal adhesive pads are not providing the required performance. Even with thermal glue, the results are not acceptable.

Does anyone know which material Deciso has used to provide an acceptable thermal conductivity between the CPU and the heat-sink? To my opinion, the thermal design is quite sub-optimal, because there is no controlled pressure applied in this zone (i.e., no screws or anything playing the same role).

Bonus question: if somebody knows how to check that ECC is really used, I would also be very interested. I tried with dmdidecode and with memtest86+, but no information related to memory (first) or ECC (second) could be displayed.

Best regards,
Vincent
Title: Re: Deciso DEC690: thermal design
Post by: franco on February 13, 2022, 08:23:29 pm
Did you contact support yet about your device? It would be the obvious first choice.

From a quick glance "the results are not acceptable" are impossible to verify given you have presented no reference points like what temperature reading you have (and how you gathered it) and what value you would think is "acceptable".


Cheers,
Franco
Title: Re: Deciso DEC690: thermal design
Post by: vlorentz on February 14, 2022, 12:25:08 am
Thank you franco.

I can give the precision, since I have 2 identical devices, and I have only opened and upgraded one, to ensure that it performs well, before I upgrade the second one.

The temperature on the non-upgraded (i.e., never opened) DEC690 is in the range of 68-70°C. The temperature of the upgraded DEC690 unit was (before I have opened it) between 70-72°C. After having opened, upgraded, and closed it again, it now has 75°C if I use a mechanical tool to press the heat-sing onto the CPU, and it displays 99.9°C if I do not press it... This is what I mean with "Not acceptable".

My question would be: is there somewhere a description how to reclose the enclosure and obtain a good cooling performance? How to proceed? Which kind of thermal adhesive was originally used?

Best regards,
Vincent