RT-AC87U running hot.

[LaPilot]

New RT-AC87U with Merlin 380.64_2 was running hotter then I would like, even though 87c (188F) is within normal operating temperature. I figure cooler temps will prolong life of the components.

I had a laptop cooling pad but it draws a 550 ma from the USB 2.o port, which is higher than I like. So I fabricated a mount using a 120mm 12vdc case fan. The mount is made out of wood, with the fan mortise in from the bottom, and the top is mortised for outflow wind channels towards each side of the RT-AC87U vents. The 12vdc fan is running great and quieter off the 5v USB 2.0 port on the router.

Net results, before fan temp 87C (188F) down to 62C (145F) using less than 80ma, and practically whisper quiet.

 

[hggomes]

This topic was discussed legions of times now, you don't need active cooling at all on the router, documentation shows the CPU TJMAX value is 125Cº, you are too far away from it.

Your concern about the components lifetime will result on better temperatures but will void the router warranty, quite a contradiction for something definitely not required...

 

[LaPilot]

I wasn't aware this was discussed previously.

How will passive cooling void the router warranty? Router is only sitting on a platform with a fan, and USB current is far less than an external drive current demand. Nothing has been altered or opened on the router?

 

[hggomes]

Not your case but most of the ppl open the router and installs a fan inside / on the case, which voids warranty, but in any case you don't really need it, though it doesn't hurt.

 

[pete y testing]

i have to agree the 87u does run warm but nothing above normal parameters , the issue for most is the fact they can see the temps and freak out thinking man 87c is hot when its actually normal , its what happens when you give laymen too many tools ( they get themselves in trouble )

 

[DanielCoffey]

Out of interest, what is your ambient temperature? It is a fair bit hotter than my 87U.

At an ambient of 24C I am showing 44C (2.4GHz), 70C (5GHz), 75C (CPU) and all I have done to it is stand it on four small plastic feet.

 

[ColinTaylor]

At an ambient of 24C...

In Edinburgh, in winter! Blimey, what's your central heating bill like.

 

[DanielCoffey]

I had the dehumidifier on to help dry some laundry so that helped warm the room somewhat but perhaps I should calibrate the sensor. It is just a digital Air temp sensor from my Aquaero6 and I have never calibrated it - it just helps measure air vs water delta for fan control.

EDIT : Checked the temp and it was 24C in that room despite being 8pm. It was south facing with big windows and had heated up lots during the day. Due to the good insulation it hadn't cooled down and the dehumidifier was helping warm the room a little too. The floor was nice and warm.

 

[xeqw]

It is normal, the Broadcom cpu is still on 40nm(higher profit margin?), comparable Qualcomm cpus are 28nm and therefore cooler.

 

[hggomes]

You are looking on old models, do check BCM4908 model available on next ASUS router (GT-AC5300), it's 28nm lithography.

 

[hggomes]

How about Broadcom 16nm?

https://www.broadcom.com/company/news/product-releases/2230131

https://www.broadcom.com/products/embedded-and-networking-processors/knowledge-based/bcm15k

https://docs.broadcom.com/docs/15000-PB100

 

[Marius Mihasan]

I resurrect this old topic with my solution for cooling the RT-87U router - I placed it on a DeepCool N300 laptop stand that has a 200 mm fan powered by USB. Additionally, I have added a potentiometer (I think) and now I can reduce the fan speed for lower noise. Look good on my desk and the it is rather quite. The temperatures dropped dramatically, from 80ish to 60ish Celsius.

 

[skeal]

I resurrect this old topic with my solution for cooling the RT-87U router - I placed it on a DeepCool N300 laptop stand that has a 200 mm fan powered by USB. Additionally, I have added a potentiometer (I think) and now I can reduce the fan speed for lower noise. Look good on my desk and the it is rather quite. The temperatures dropped dramatically, from 80ish to 60ish Celsius.

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I have almost the exact same as you. My laptop cooler is really quiet so I didn't have to throttle it down. I too get great temperature readings. Nice work there!!