Cooling the Linksys E3000

A short time back I was shopping around for a new router. After some comparison shopping I decided on the Linksys E3000. (UPDATE: Read more on this at Cooling the Linksys E3000 – Part 2 – Inside the box)

However, I was having issues with my Wii randomly dropping off the wireless network. I started troubleshooting and accidentally happened on something that bothered me: This router got HOT. By hot I mean I checked it with my infrared thermometer and I got a reading of 61C from the bottom of the router. That’s well above it’s operational temperature rating of 40C.

First, a note on my configuration:

  • DD-WRT v24-sp2 (12/19/10) big (e2k-e3k)
  • 2.4ghz  and 5ghz access points, both in use
  • A single gigabit device on the wired lan.

I had a good deal of network activity going at the time, so I took most of the devices off the network, powered off the router for about 5 minutes, turned it back in and checked again. No measurable difference in temperature after about a  minute of operation.

My concern was that the router was simply too hot to continue operating like this. I was afraid of chipset failure.

I started in on a mod idea, with a couple of points:

  • The router needed to be cooled quietly
  • The router needed to be cooled in a way that wouldn’t void the warranty in case I ended up RMAing it.

I initially thought of driving a fan from the DC-in connector, but the barrel shape made it difficult to come up with a clean mod, and at 12 volts, it could get a little noisier than I wanted it to be. I wasn’t using the USB port, and that’s an easy 5v supply to a fan, clean and easy.

So I started with a simple USB-to-fan cable. Pulling the 5v supply off the USB port and to a fan connector was easy, and after a quick check with the multimeter said it was good to go. It worked great, but I found out that unfortunately none of the fans I had lying around ran at 5v; they were all 12v fans. I would have to buy a fan for this.

I figured a 120mm fan would give me good air flow at a low noise rate, along with covering most of the bottom of the router. A quick search turned up a Coolerguys 120mm USB fan. A 5v fan with a USB connector to boot. Oh well, I still get to keep my cable for another project :)

So I ordered the fan. It arrived quickly (not quickly enough, I was impatient! ;) ), and I started in on making it look nice.

Removing the grill from the fan was the first step, and it came off easily with a #2 Philips screwdriver.

I had some adhesive foam feet lying around from something else, and cutting them in half and stacking three gave me a nice fit with the finished feet measuring 25x20x28mm.

I added some 4mm rubber feet to the bottom of the fan to give it intake room, and test fitted it. It couldn’t have worked out better. The fan fit neatly under the router and ran quietly — I could barely hear it even when the room was completely quiet. The 4mm rubber feet allowed enough intake room under the fan, even though the fan could have easily moved more air with more of an intake space.

The result? A reading of 30CThat’s a 31C drop in surface temperature! Of course, if you do this, make sure the fan is blowing up into the bottom of the router; not down.

The Wii? As it turns out, it was in a spot where it got terrible signal to begin with. A wired adapter fixed it’s issue.

My thought at the end of this was “Why didn’t Linksys consider something like this from the beginning?” followed by “How soon until our home networking equipment has to be fan cooled?

Here’s all the photos from the mod project:

Have a Linksys E3000? Have your own cooling mod idea to share? Please feel free to share your thoughts in the comments below!


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  1. #1 by Kevin on April 4, 2011 - 7:46 am

    Great idea, I did the same and my router performance has improved significantly. Previously, my E3000 was slowing down under the heavy load of online gaming. Plus the fan is quiet.

  2. #2 by Ken on October 18, 2011 - 11:10 am

    Thanks Mike. The fan really helps cool down the router. I just wanted to add that I was able to put a 2 port USB hub and hook up the fan and usb drive to the router.

    • #3 by Mike on October 18, 2011 - 6:19 pm

      Very nice. I didn’t even think of that. Thanks so much for sharing!

  3. #4 by dings on November 29, 2011 - 6:21 am

    Nginx seems to have missplaced your images ;)

    • #5 by Mike on November 29, 2011 - 7:25 am

      You’re right! What a mess it made… Should be all fixed now. Thanks so much for bringing that to my attention. :)

  4. #6 by dirk on January 1, 2012 - 6:26 am

    Thanks for sharing. I noticed that the operational tempererature with TomatoUSB is lower than with DD-WRT. Have a look at the systems load:
    – TomatoUSB: Almost zero
    – DD-WRT: Takes long after boot to settle and load is never zero (or seldom)

    Bottom Temp: 51°C resp. 40°C if the E3000 stands upright

    Actually I have this build installed

  5. #7 by fzee on January 22, 2012 - 11:57 am

    very cool. have been thinking about E3000 but heard bad things about heat issue. One follow up — the external fan just sucks the air downward and blow it down towards ur desk?

    since heat rises and u really don’t look at the face of a router anyway, would the heat issue be partially mitigated if u just flip your router face down allowing the heat to rise through the vent holes?

    • #8 by Mike on January 22, 2012 - 12:04 pm

      I have the fan blowing up. This blows air up through the holes in the bottom of the router, and it comes out through the top (under the “ridge”) of the router.

  6. #9 by Eddie on January 23, 2012 - 3:38 pm

    good solution, How did you get the fan to stick to the bottom of the router? did you use screws that screwed into the router bottom?

    • #10 by Mike on January 23, 2012 - 4:37 pm

      It doesn’t, actually. The router sits on top of the fan. You could use some adhesive pads or small screws if you wanted, but be mindful of the PCB if you decide to use screws.

      • #11 by Eddie on January 23, 2012 - 4:44 pm

        Thanks Mike!, I just picked up a E3000 and will be flashing it shortly with DD-WRT. Good to know about the heating problems!

  7. #12 by joevirginia on July 22, 2012 - 6:41 am

    been having problems with wi fi and Roku dropping out. discovered also by accident how hot the linksys was.

    thanks for both of your blogs and the independent research. disappointed since I paid more for what I thought would be a premium router.

  8. #13 by Jonas on October 28, 2012 - 11:14 pm

    I read this article about overheating and have to say, there is actually no evidence of overheating. The problem was eventually cured by changing to a wired adapter for the wii.

    Just FUD.