Asus AC68U vs Asus AC88U range, temperature and stability

[RMerlin]

Also, your Intel CPU has low-power states, and Speedstep. The BCM4709 doesn't. Clock stays always at 1 GHz.

Try running prime95 on your Intel, and watch its temperature...

 

[sfx2000]

The BCM4709 isn't "just" a CPU, it also contains other blocks such as the BCM5301x. the USB controler, etc... It's a complete SoC, you can't compare that with a plain CPU.

The C2358 is a complete SoC as well - with much of the same goodies as the broadcom chip, actually more with 4 1GB NIC's built in - the switch traffic is low impact, the cores are where the work is...

 

[sfx2000]

Also, your Intel CPU has low-power states, and Speedstep. The BCM4709 doesn't. Clock stays always at 1 GHz.

It's clock min is 1.2GHz, clock max is 2.0Ghz, it's spends most of the day at 1.2...

 

[Wutikorn]

Replace that with a cheap heatsink, and put a thermal pad instead of thermal compound. Put it slightly askew, and watch your CPU temperature sky rocket...

The BCM4709 isn't "just" a CPU, it also contains other blocks such as the BCM5301x. the USB controler, etc... It's a complete SoC, you can't compare that with a plain CPU.

Based on the temperature you can feel by touching the case, I'd say the temperature looks right to me. And people's results when they just replace the thermal pad with proper compound showed a temperature drop totally in line with what I would expect.

RMerlin, can I ask you sth about Asus AC68U with AsusWRT Merlin? I wonder if Asus AC68U has wifi smart connect in Merlin firmware? As I don't see it in stock firmware, and I want just one name that is for both band.

 

[System Error Message]

RMerlin, can I ask you sth about Asus AC68U with AsusWRT Merlin? I wonder if Asus AC68U has wifi smart connect in Merlin firmware? As I don't see it in stock firmware, and I want just one name that is for both band.

Smart connect is for those triband wifi routers. The AC68U is only dual band.

Also, your Intel CPU has low-power states, and Speedstep. The BCM4709 doesn't. Clock stays always at 1 GHz.

Try running prime95 on your Intel, and watch its temperature...

Try running prime95 on a BCM4709

 

[Wutikorn]

Smart connect is for those triband wifi routers. The AC68U is only dual band.

Can't it just know to use 5GHz channel when it's compatible? Now when many people connect to my wireless router, most of them ask which one should he/she choose.

 

[System Error Message]

5Ghz is different to 2.4 Ghz. When you have 2 5Ghz radios than they have the same signal integrity but between 2.4 and 5Ghz the signals are different so the client can switch between them. Smart connect is meant to balance the traffic between the 5Ghz radios and probably 2.4Ghz.

 

[pete y testing]

Smart connect is meant to balance the traffic between the 5Ghz radios and probably 2.4Ghz.

the 88u has smart connect for its 5 gig and 2.4 gig

 

[sfx2000]

Smart connect is for those triband wifi routers. The AC68U is only dual band.

Try running prime95 on a BCM4709

Again - I'm thinking the calculation is off, perhaps as much as 2x - the BCM2837 in the RaspPI3 under heavy load might hit 45C, and that's at 1.2GHz with 4 A53 Core and a Video Processing Unit.. and it's not a FCPGA (flip chip). And that is without a heat sink...

Would be interesting to get an RT-AC68U on a bench with a thermistor and a data logger to see just how hot it's actually running - folks to date have been reporting what the Asus SW is seeing..

 

[Wutikorn]

the 88u has smart connect for its 5 gig and 2.4 gig

With its stock firmware? I hope Asus AC68U will get Smart Connect pretty soon too.

 

[System Error Message]

Again - I'm thinking the calculation is off, perhaps as much as 2x - the BCM2837 in the RaspPI3 under heavy load might hit 45C, and that's at 1.2GHz with 4 A53 Core and a Video Processing Unit.. and it's not a FCPGA (flip chip). And that is without a heat sink...

Would be interesting to get an RT-AC68U on a bench with a thermistor and a data logger to see just how hot it's actually running - folks to date have been reporting what the Asus SW is seeing..

On stock the AC68U if you got the CPU to 100% the temperature can get near 100C or above without active cooling. Imagine at 1.2Ghz it will definitely overheat. Intel CPUs on the other hand just put a massive heatsink and they wont overheat. On intel dual core CPUs, the desktop iseries a massive heatsink without the fan is actually enough to keep it cool if the case has fans/there is good airflow. I once ran the desktop AMD bulldozer with just the big heatsink and no cpu fans, case had good airflow so i got around 60C. Many prebuilt systems just have poor cooling and many intel CPUs are designed to run up to 90C with turbo and than clock down ever since sandybridge. If you had good cooling you could run turbo the whole time on intel CPU. The Asus AC68U has some issues with their cooling requiring either active cooling or tearing it down to make sure the thermal pads and heatsink are all mounted properly. Dont forget that the broadcom's A9 is made on a larger process than the A53 used in raspberry pi and these chips by themselves arent used at 100% all the time but with a heatsink and good airflow you can run the CPUs at 100% all the time. If in an enclosed space the raspberry pi will overheat. Doesnt everyone remember how HPs always overheated?

The issue with both the broadcom and intel is just the manufacturer having poor cooling but the reference design is usually much better. The same can be said for phones and tablets, developer ones despite being bulky have more battery, all the hardware features and better cooling than the retail ones. The developer tablet i have that uses qualcomm's 8 core 64 bit ARM has enough battery for between 1-4 days depending on whether i watch videos 24 hours a day or use it lightly for some internet and notes. All the retail tablets based on that chip have less battery and RAM and they end up about the same price. The only downside with developer is that the firmware isnt as good function wise or in terms of bugs but it is lean without bloatware except for some developer related apps.

I still would like to see the broadcom chip running prime95, previously it was a benchmark for x86 so it would be interesting to benchmark other architectures.

 

[pete y testing]

With its stock firmware?

yes

I hope Asus AC68U will get Smart Connect pretty soon too.

i doubt it

 

[cobra_shipwreck]

If you want active cooling go with a mid level cisco router. Go with one of the retired models and you will have an actively cooled device at a fair price, but would still need a separate device for wireless.

Alternately just moving air across and out of the area where the equipment is will help as well or a mini room air conditioner will address any heat concerns. You want the ambient temperature around the device around 68 at a maximum temperature.

 

[sfx2000]

On stock the AC68U if you got the CPU to 100% the temperature can get near 100C or above without active cooling. Imagine at 1.2Ghz it will definitely overheat.

You're going off the stock firmware - and that's where I'm saying the bug is...

Seriously... I've done OEM designs across different CPU archs - including ARM's, and the numbers don't make sense...

Hence the thought that this is a bug in AsusWRT...

If the SoC was that hot, you would not be able to touch the housing - it wouldn't be comfortably warm to the touch, it would be scalding hot... stick your finger in a pot of boiling water...

 

[System Error Message]

You're going off the stock firmware - and that's where I'm saying the bug is...

Seriously... I've done OEM designs across different CPU archs - including ARM's, and the numbers don't make sense...

Hence the thought that this is a bug in AsusWRT...

If the SoC was that hot, you would not be able to touch the housing - it wouldn't be comfortably warm to the touch, it would be scalding hot... stick your finger in a pot of boiling water...

heat capacity is one factor so something can have a high temperature but not be hot because of the heat capacity. Its an important factor in choosing heatsinks too.

 

[DomFel]

I'm going to buy a router in a month, and I am choosing between Asus AC68U and Asus AC88U. I currently have Buffalo WZR-HP-AG300H, and I found out that its range is just there, but it is not stable. I just want stable connection at 20Mbps while I have wireless N devices. My internet speed is 20Mbps/7Mbps. I will have WD DL2100/ 1-2 torrenting devices/ a 720P Wireless IP Camera and 5-30 web-surfing devices. I will use Ai-Protection, adaptive QOS and OpenVPN(Max speed is 7Mbps due to my Internet speed). I am concern about heat, the temperature can goes up to 35-40C in the room. The router will be put in a place that nothings are around. I am also concern about stability. I have to restart my Buffalo router weekly in order for it to work properly, but I don't want to do that in the new router. And I wonder if I should use Asus Merlin firmware or not. So which router should I buy?

Living in the Middle East?? If you're planning to use OpenVPN I suggest Tomato, way more stable.
35-40C won't be a big problem, router will most likely hit 85/90C. It's fine, but a small usb fan connected to it will lower the temperature by about 10C making it more stable.
(56U here, overclocked to 1200mhz, 5ghz only wifi, 74C in a room with AC set to 26C).

 

[kvic]

Would be interesting to get an RT-AC68U on a bench with a thermistor and a data logger to see just how hot it's actually running - folks to date have been reporting what the Asus SW is seeing..

Here is a thermal image for RT-AC87U. Compared to what ppl reported on this forum, readings from FW and by instrumental measurement are pretty close.

Perhaps Tim shall invest a little money to include thermal images in future reviews. Make it look like rocket science to his audience.

 

[Wutikorn]

yes


i doubt it

How come? I thought that if they could make in one router, the other would be easier to do. But Asus AC68U is becoming older and older versions.

Living in the Middle East?? If you're planning to use OpenVPN I suggest Tomato, way more stable.
35-40C won't be a big problem, router will most likely hit 85/90C. It's fine, but a small usb fan connected to it will lower the temperature by about 10C making it more stable.
(56U here, overclocked to 1200mhz, 5ghz only wifi, 74C in a room with AC set to 26C).

Yeah, Southeast Asia, I found the best room for this router which should not go higher than 30C. Will Tomato voids the warranty if I don't overclock?

If you want active cooling go with a mid level cisco router. Go with one of the retired models and you will have an actively cooled device at a fair price, but would still need a separate device for wireless.

Alternately just moving air across and out of the area where the equipment is will help as well or a mini room air conditioner will address any heat concerns. You want the ambient temperature around the device around 68 at a maximum temperature.

I already got Asus AC68U, haven't thought about Cisco mid router before.

 

[RMerlin]

I wonder if Asus AC68U has wifi smart connect in Merlin firmware? As I don't see it in stock firmware, and I want just one name that is for both band.

No.

 

[RMerlin]

Hence the thought that this is a bug in AsusWRT...

And as I keep telling you, this code is from Broadcom, not from Asus. So unless you're going to tell us that Broadcom's own code is unable to read the temperature of their own hardware, I'd say the value returned is correct.

https://github.com/RMerl/asuswrt-me...inux-2.6.36/arch/arm/plat-brcm/bcm5301x_dmu.c

The whole source file even has Broadcom's Copyright header. It comes straight from the Northstar platform SDK.