Asus RT-AC3100 (AC88u) very hot. Any one have installed copper shim in it?


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My Asus RT-AC3100 (similar to AC88u) is very hot. If I dont use any method to cool it down, it will reach very high (ambient 34):
Legend: 2.4 GHz - 5 GHz - CPU
Current Temperatures: 50 °C - 55 °C - 75 °C

I use a old server Delta 90mm 12v fan, (AUB0912VH) suck air out of the top. and temps drop significantly for the CPU and 2.4G
Legend: 2.4 GHz - 5 GHz - CPU
Current Temperatures: 42 °C - 49 °C - 55 °C

I am still not happy, because in hot summer the ambient temperature can reach as high as 40 in the router room, and good idle temperature for electronics device is about 50. I read some where here, people can change the thermal pad of the CPU to copper shim and can passively down the temp ~20°C, and after combining copper shim +external fan, the CPU temp down to ~45 °C easily. But I dont see any copper shim installation guide for AC88U or AC3100. So if you see somewhere a guide to do that, or if you have experience with that. For example: copper shim thickness, should we replace also the upper thermal pad with copper shim (the pad sits between the shield and heat sink), and how to prey the shield without deforming it. Please help.

I found this link about AC88u teardown, very good for preparation:

Thank you!
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Part of the Furniture
75C CPU in 34C room is not very hot. The original cooling solution is good, you don't need to do anything.


Part of the Furniture
That is a very cool running RT-AC3100.

My customer has an RT-AC3100 running for over 18 months in ambient 35C (kitchen) temperatures and average around 96C.

Another customer with an RT-AC68U is also running at 94C temperatures without issues for over three years now.

The SoC is rated at 120C, even if a core may shut down somewhere above 100C.

This is how these are designed and built.


Part of the Furniture
For me it is very hot. I dont think the router will last long with that temperature.

If you don't plan forced air circulation, shimming the ICs won't change much. You'll see lower CPU temperature, but because of the better thermal transfer the heatsink temperature will increase. If nothing helps with heat dissipation, the heat stays inside the router, just in different places. Your CPU will be cooler, but the rest of the components hotter. I wouldn't bother disassembling this router. I would place it on top of a small laptop cooling pad instead.

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