I want hear from you what is the good idea to reduce the temperature of the modem (Snapdragon X75 - Quectel RM551-GL) ...
Where my modem is reaching from 60c - 68c ... there is heatsink copper on the modem
Should I order fan with this temp ? or should don't as per operation Temp by manufacture
Usually a cpu is below 70 when cooled. You can run htop and check if the cpu is throttling down when in operating temp. If it isnât throttling down then a cooler wonât make it go faster.
Op temp for normal temp version is up to 75°C so we are still inside specs.
Extended version is 85°C.
Over that there is the environmental standards (for highest operating temp) âindustrial standardâ with 125° and over that we have âmilitary (and auto industry) standardâ with 155°.
This is pretty much silicone chip standard operating temperatures and their respective name.
The thing here is that we donât know what actual model is installed if it is the standard operating temp model or extended temp model. We talk about two different hardware chips in the same family here with different part numbers!
At best it is text coded on top of the chip under the cooler but you need the actual datasheet to know what that code actually say.
The most likely scenario what is installed is to look at the lower operating temperature.
If the device is made to be used outside then it is pretty much guaranteed to have the extended temp range to survive down to -40°C.
-30°C (or sometimes -20°C) isnât actually defined in any electric environmental standard, so that is a strong clue that the ânormalâ temp range is something the manufacturer have made up for their lower quality chips made for cheap inside home usage.
All available environmental standards have either 0°C for normal, -40°C for extended and industry or -55°C for mil, aerospace and auto as lower temp range.
+75°C is a little anomaly also because usually it is +70°C, but not as big anomaly as -30°C!
I think you should consider using the case itself as the heatsink, then add a fan outside if necessary. As to how...maybe heat pipes or heat straps?
Also, whoever's saying it's not "thermal throttling", please go read the thermal management guide from Quectel and do your own testing. Those power amplifiers are no joke, even with envelope tracking.
Itâs black which mean it dissipate heat as fast as possible.
It has convection cooling, the ribs on the surface.
I suspect it is aluminum.
But to make the cooling work as optimal as possible this kind of case and thermal solution must be mounted on a wall with the ribs on the case mounted vertically.
