Review RT-AC66U vs RT-N66U

[MonkY]

There is nothing wrong with the amount of heat generated, the hardware was designed for this.

Well, i am sure it's not that well designed if i had to move my RT-N66U in a much cooler area, because of overheating. And i suppose you know the designed board had initially an active cooler, which was later removed/replaced by only aluminium heatsink (which i think it's not enough).

My former WRT320N was actually running hotter than this, leaving the wooden shelf on which it sat quite warm to the touch. My cablemodem also runs much warmer than my RT-AC66U.

I believe you. But i also owned like 20 D-Link routers (and installed a few hundreds of them) and none of them was even close to half the heat N66U is generating.

Can you please just compare the temperature between RT-AC66U and RT-N66U? Maybe they have improved the thermal conductivity on the newer model. I'm about to sell my N66U (because of this issue - it gets at arround 48-50 degrees Celsius on outside, specially on the metal frame of the ports), and i am hoping the AC66U is much cooler.

Thanks in advance!

 

[RogerSC]

Well, i am sure it's not that well designed if i had to move my RT-N66U in a much cooler area, because of overheating. And i suppose you know the designed board had initially an active cooler, which was later removed/replaced by only aluminium heatsink (which i think it's not enough).

I believe you. But i also owned like 20 D-Link routers (and installed a few hundreds of them) and none of them was even close to half the heat N66U is generating.

Can you please just compare the temperature between RT-AC66U and RT-N66U? Maybe they have improved the thermal conductivity on the newer model. I'm about to sell my N66U (because of this issue - it gets at arround 48-50 degrees Celsius on outside, specially on the metal frame of the ports), and i am hoping the AC66U is much cooler.

Thanks in advance!

Are you using that funky stand that Asus gives you with the router? If you aren't, it will run cooler semi-vertical. I've also had routers that ran hotter, like the Linksys E-4200, and there was no built-in vertical option for that one. You had to kind of prop it up somehow to promote air circulation. I'm pretty happy with the heat situation on this one, and glad it doesn't need a fan (like the E-4200 did).

 

[MonkY]

Are you using that funky stand that Asus gives you with the router? If you aren't, it will run cooler semi-vertical. I've also had routers that ran hotter, like the Linksys E-4200, and there was no built-in vertical option for that one. You had to kind of prop it up somehow to promote air circulation. I'm pretty happy with the heat situation on this one, and glad it doesn't need a fan (like the E-4200 did).

No, i can't use the "funky stand" (not enough space to keep it vertically). Btw, when you say you are happy with it, are you referring to AC66U or N66U?

 

[RogerSC]

No, i can't use the "funky stand" (not enough space to keep it vertically). Btw, when you say you are happy with it, are you referring to AC66U or N66U?

I am talking about the rt-n66u...but I would think that the rt-ac66u would be similar enough, heatwise. I tried my router horizontally first and wasn't happy with the heat situation, then used the stand and it was fine. So if you can find a place for it where you can use the stand, I think you'll be more satisfied. If not, maybe a laptop or netbook cooling pad would be helpful? They're pretty quiet, and can be powered by a USB port. Just a thought...sometimes elevating a router by putting some open supports under it can also help, to allow more airflow around the surface. That also helped with my Linksys E-4200.

I have my router on the top shelf of the bookcase at the back of my computer desk, so there's plenty of room for it to be vertical.

 

[RMerlin]

Well, i am sure it's not that well designed if i had to move my RT-N66U in a much cooler area, because of overheating. And i suppose you know the designed board had initially an active cooler, which was later removed/replaced by only aluminium heatsink (which i think it's not enough).

I believe you. But i also owned like 20 D-Link routers (and installed a few hundreds of them) and none of them was even close to half the heat N66U is generating.

None of them had a 600 MHz CPU, 256 MB of RAM and full triple-stream dual-band radios however. And yet, to quote a colleague of mine, "DLink routers are dropping like flies here". At his place he would always buy a bunch of spare ones since they were totally unreliable. He was a purchasing manager for a retail chain.

As for myself, I banned DLink routers from the store where I work due to having too many reliability issues with their products. I got us switched to Linksys, before eventually switching to Asus products.

The chips are designed and configured to be able to reach over 70C (unless it was 80C, I can't remember), at which point they will throttle down in speed to avoid damage. I have never seen my router get above 61-63C myself during the warmest days of summer (and I have no AC, so it can get quite hot in here).

Can you please just compare the temperature between RT-AC66U and RT-N66U? Maybe they have improved the thermal conductivity on the newer model. I'm about to sell my N66U (because of this issue - it gets at arround 48-50 degrees Celsius on outside, specially on the metal frame of the ports), and i am hoping the AC66U is much cooler.

Thanks in advance!

Internal temperature of both N66U and AC66U are about the same for me. Maybe slightly lower on the 2.4 GHz band with the AC66U vs N66U, but only a few degrees. Could be just a matter of thermal paste.

Using the included stand does help if you still want to find ways to reduce the temperature. But personally I would not worry about it.

 

[Geraner]

Thanks for the comparison! As you have tested both RT-AC66U & RT-N66U, can you please tell us how is the heating issue? Did Asus solved the problem (although the internal design seems the same). Is the new AC66U getting the same heat amount as N66U does? My N66U really worries me, as it's getting really, really hot!

Well, I actually never experienced any heating issues with my RT-N66U.
Of course the router got a bit wormer than my old D-Link router. But not so hot that I would burn my fingers when putting them on the router.

The same for the RT-AC66U. Yes, the router is a bit warmer than the old D-Link router. But compared to the RT-N66U I can't see any difference. Keep in mind that I didn't experienced any problems with that the router itself is a bit more hot. - I'm impressed by the performance of both routers, the RT-N66U and the RT-AC66U. So I can understand that such powerful products can get a bit more hot then others.

 

[MonkY]

None of them had a 600 MHz CPU, 256 MB of RAM and full triple-stream dual-band radios however.

Strange enough, we have these days Quad Core CPU's running at 1.6 - 2.Ghz (on smartphones, tablets, etc.), plus 2GB RAM, plus Quad Core GPU, that don't heat up at all (or not even close to the 600Mhz CPU Asus uses).

And yet, to quote a colleague of mine, "DLink routers are dropping like flies here". At his place he would always buy a bunch of spare ones since they were totally unreliable. He was a purchasing manager for a retail chain.

Maybe he talks about the cheap ones. We have Dlink's that are still working even after 6-7 years. I miss the day when DLink was giving 10 years warranty to all their routers!

The chips are designed and configured to be able to reach over 70C (unless it was 80C, I can't remember), at which point they will throttle down in speed to avoid damage. I have never seen my router get above 61-63C myself during the warmest days of summer (and I have no AC, so it can get quite hot in here).

The temperature i was getting (when not even fully used)... the 48-50 Degrees Celsius was on the outside. So i think it's logical to imagine that 50 degrees outside would mean arround 70C on the chips (or even more). And that's on a winter day... I'm worried about a summer day, without A/C...

But.. maybe i'm worried to much. I just hate overheating components... High temperature is never too good for them, specially on a long term...

 

[RMerlin]

Strange enough, we have these days Quad Core CPU's running at 1.6 - 2.Ghz (on smartphones, tablets, etc.), plus 2GB RAM, plus Quad Core GPU, that don't heat up at all (or not even close to the 600Mhz CPU Asus uses).

Try taking off that large heatsink you have on your CPU. You'll see the true meaning of "toasted" within a second Also, that CPU runs at around 1.4 GHz only while in idle (sometimes even lower). The high-end Intel CPUs can dissipate up to 130W of power. That's about 10x more than your whole router - and we are only looking at the CPU, without the RAM, network card, etc...

Maybe he talks about the cheap ones. We have Dlink's that are still working even after 6-7 years. I miss the day when DLink was giving 10 years warranty to all their routers!

It's been a few years so I can't recall what they were buying, but I think it was mid-range products on average.

My own personal experience with a DLink router has been pretty bad as well. I replaced it with a WRT54G before it could die on me.

The temperature i was getting (when not even fully used)... the 48-50 Degrees Celsius was on the outside. So i think it's logical to imagine that 50 degrees outside would mean arround 70C on the chips (or even more). And that's on a winter day... I'm worried about a summer day, without A/C...

Enable the telnet server on your router, and run the following commands over Telnet:

wl -i eth1 phy_tempsense
wl -i eth2 phy_tempsense

Divide each value by 2, and add 20 to them. This will give you the internal temperature of the 2.4G and 5G radios.

 

[Pierino]

Or install Merlin fw and go to tools and read the temp there.

 

[RogerSC]

Merlin is quite right about the quad core phones...take a look at CPU spy or betterbatterystats. I find that my phone spends about 5% of its time at 384MHz, about 93% in "deep sleep", and 0% (approximately) at 1512MHz.

If it were different, my battery wouldn't last and this would a *really* hot phone *smile*. Of course, I don't watch movies or play graphics intensive games on my phone. But it is still a much faster phone than the iPhone I used to have.

 

[MonkY]

Merlin is quite right about the quad core phones...take a look at CPU spy or betterbatterystats. I find that my phone spends about 5% of its time at 384MHz, about 93% in "deep sleep", and 0% (approximately) at 1512MHz.

So what you are actually saying is that your router is always running at full speed, while your smartphone isn't? Nice one

Anyway, after 4 days of idle, my RT-N66U with CPU Load (1 / 5 / 15 mins) 0.00 / 0.00 / 0.00, is still running HOT. Going to exchange it for the second time. If the third one runs the same, i'll have to say goodbye Asus!

Of course, I don't watch movies or play graphics intensive games on my phone.

Based on the stats you wrote, with 93% in deep sleep, you are NOT actually using it at all

But it is still a much faster phone than the iPhone I used to have.

My iPhone 5 is definitively faster than my Galaxy Note 2. Talking about optimization vs hardware (dual core vs quad core, 1.3Ghz vs 1.7Ghz, 1GB RAM vs 2GB RAM). But that's off-topic.

Btw, is there anything custom for RT-AC66U (like TomatoUSB or DD-WRT was for RT-N66U) or just Asuswrt-Merlin?

 

[RMerlin]

Anyway, after 4 days of idle, my RT-N66U with CPU Load (1 / 5 / 15 mins) 0.00 / 0.00 / 0.00, is still running HOT. Going to exchange it for the second time. If the third one runs the same, i'll have to say goodbye Asus!

I think you missed the point. The fact it runs hot is not a sign of anything abnormal. It's designed that way. And unless you are actually experiencing stability issues caused by that heat, there is nothing wrong there.

And for the record: my former Linksys WRT320N was hotter than my RT-N66U and RT-AC66U, despite the fact it was single radio, and with a slower CPU. And all three routers have always been perfectly stable.

My WDTV Live was also running quite warm. The metal part of any plugged USB disk would become uncomfortable to the touch.

Power dissipation is a perfectly normal thing in modern microelectronics. It's part of the design specs. A high-end Intel CPU for instance can dissipate as much as 130W as heat, and it's documented in Intel's technical specifications. If someone feels like digging up the spec sheets for the chips used in those routers, they will probably carry actual values as to the amount of power normally dissipated.

 

[MonkY]

I think you missed the point. The fact it runs hot is not a sign of anything abnormal. It's designed that way. And unless you are actually experiencing stability issues caused by that heat, there is nothing wrong there.

Well, both Linksys EA6500 and Asus RT-AC66U are using the same Broadcom BCM4706 CPU (at 600Mhz), and while Asus is using a huge aluminium pad for cooling, the Linksys does not. And yet, the EA6500 is just warm, while RT-AC66U get's hot! So, imo i think there is a flaw in Asus design.

P.S. I have only checked the EA6500 in store, so i might be wrong and the unit could get a lot hotter in a standard room and setup. Maybe somebody that owns the EA6500 can compare the temperatures with RT-AC66U. Thanks!

 

[RMerlin]

Well, both Linksys EA6500 and Asus RT-AC66U are using the same Broadcom BCM4706 CPU (at 600Mhz), and while Asus is using a huge aluminium pad for cooling, the Linksys does not. And yet, the EA6500 is just warm, while RT-AC66U get's hot! So, imo i think there is a flaw in Asus design.

P.S. I have only checked the EA6500 in store, so i might be wrong and the unit could get a lot hotter in a standard room and setup. Maybe somebody that owns the EA6500 can compare the temperatures with RT-AC66U. Thanks!

Would be good to know what clock rate Linksys are using as well.

Someone with an EA6500 running DD-WRT or Tomato could also retrieve the radio temperatures through Telnet - that would give us an objective point of reference.

 

[RogerSC]

Originally Posted by RogerSC
Merlin is quite right about the quad core phones...take a look at CPU spy or betterbatterystats. I find that my phone spends about 5% of its time at 384MHz, about 93% in "deep sleep", and 0% (approximately) at 1512MHz.

So what you are actually saying is that your router is always running at full speed, while your smartphone isn't? Nice one

Originally Posted by RogerSC
Of course, I don't watch movies or play graphics intensive games on my phone.

Based on the stats you wrote, with 93% in deep sleep, you are NOT actually using it at all

What I was saying was that my quad-core phone spends very little time running at top speed. You supplied the rest.

And if you take (100% - 93% = 7%) and multiply that by by 24 hours, you get a "usage" of about 1.7 hours for the day. That's not exactly "not using my phone at all". However, using the tools that are available for Android phones that I mentioned, I do make sure that when I'm not using it, it's using minimum battery. When I had an iPhone, I couldn't do that kind of tuning, it was much more trial-and-error, which is one of the reasons that I now have an Android phone.

 

[TonyH]

Hi,
I just read temperature of my AC66N case on a stand using laser thermometer aiming top right corner. 41 deg. C. Merlin f/w tool shows both radios temp are at 54 deg. C. I don't think these readings are excessive. Personally if they go over 60 deg. C. I'd feel uncomfotable

 

[MonkY]

Hi,
I just read temperature of my AC66N case on a stand using laser thermometer aiming top right corner. 41 deg. C. Merlin f/w tool shows both radios temp are at 54 deg. C. I don't think these readings are excessive. Personally if they go over 60 deg. C. I'd feel uncomfotable

My actual AC66N shows: 2.4 GHz 56°C - 5 GHz 60°C (and that's after a night in idle, with both radios running at default 80mW). It's in the "vertical" position (with Asus stand) in an open space (on my desk). I already feel uncomfortable

 

[TonyH]

Hmmm,
I am a retired EE who spent all my life in the field from the days of vacuum tubes thru x-sisters and today's ever evolving micro electronics, nano tech. In my working days I even encountered heat caused damage making a component into molten metal soup.

Does your router smell burning or smoking or ever experienced failure due to excess heat? When I can fry my egg on my router, then I'd worry about excess heat. Either you chuck your router or install cooling fan/heat alarm jury rigged or use a commercial/mil-spec grade equipment if you are so concerned about heat. We are living in a throw away society, consumer grade things are made that way these days.

 

[njweb]

I too have same problem with RT-N66U, just would not be stable for me, I have many devices and two 8 port switches and a server and access points. unforchantly I had to return the RT-N66u

Good news i perchased the RT-AC66u and with its newest firmware its great no problems at all. It's routing is incredibly stable and fast the best I ever used and i used a lot. It's a keeper. Now I use AP's running off it and not using the wireless on it so can't comment on that.

So its handling everything flawless and i finally couldnt be happier after 20 years of going crazy. Lol

Oh now not sure if it makes a difference or how it would effect the network or router though I should mention I also updated the linux servers Ethernet from Realtek to intel at the same time as the RT-AC66U install, also turned on jumbo frames on router.
I mention this cause I had a few routers that when I connected my server to them the router would just freeze up, namely ASUS and a few others, :/ I kid you not, also many routers did not like running AP'S from them they would get flaky

The other changes you made may have helped make things more stable since the two routers are very similar (other than the AC66U having 802.11ac support).
Did you have the N66U firmware with the increased NVRAM size? That could also have made the difference (i.e. if your AC66U had it and your N66U did not).

I have an N66U and am finally about to open my AC66U after months of it sitting in a sealed box while I enjoyed my N66U.
Going to run my own comparison tests with LAN Speed Test before deciding which one to keep. The fact that the N66U may have slightly better signal levels and throughput, according to others, will play a role in my final decision.

 

[Icewind]

Well, both Linksys EA6500 and Asus RT-AC66U are using the same Broadcom BCM4706 CPU (at 600Mhz), and while Asus is using a huge aluminium pad for cooling, the Linksys does not. And yet, the EA6500 is just warm, while RT-AC66U get's hot! So, imo i think there is a flaw in Asus design.

P.S. I have only checked the EA6500 in store, so i might be wrong and the unit could get a lot hotter in a standard room and setup. Maybe somebody that owns the EA6500 can compare the temperatures with RT-AC66U. Thanks!

Hey, first post here. Looking into the AC-66u vs N66u debate as well. As per your comment re: router temp, keep in mind that while the AC-66U may FEEL hotter, that is not necessarily a bad thing. This means that the unit is dissipating the heat effectively away from the silicon.

I can only speculate on the linksys, that if it runs the same chip there are any number of other factors that may mean it feels cooler to the touch.

1) Running at a lower speed.
2) The heat is dissipated in a different area of the router that you havn't handled,
or
3) The router is not heatsinked/heatsink is much smaller, therefore less heat is dissipated. This is a BAD thing since the silicon will be running much hotter.