One or two fans to cool my WRT54GL ?

Discussion in 'Modding Forum' started by gettons, Dec 3, 2006.

  1. gettons

    gettons LI Guru Member

    Hi, I'm just a new user of forum.
    I have 3 WRT54GL :

    firewall (shorewall ) with openwrt
    access point Hyperwrt

    I wish to overclock one of mine, to speed it up to 250Mhz, just to test it, and eventually to put into my firewall customization.

    I will put some heatsink on chipset,ram and CPU and after
    I've two choice:

    1) take power from PCB (soldering the two fan wire directly behind the power connector, like other users do ) and installing ONLY one FAN 60x60x10mm to pull air OUT
    I'm not interested about pot, beacuse I'll put the router in a room dedicated to my servers

    2) using an external power adaptor and use TWO fan , pushing air INTO wrt and another pushing air OUT

    I wish to take some advices form users that have done that in a safe way.
    What is better?
    Where to put eventually the two fans?

    Thanks a lot and sorry for my bad english ( Italian user )

    One fan is enough or not?
  2. u3gyxap

    u3gyxap Network Guru Member

    If you realy want a fan - go with the single fan idea. Personaly, I would just put a nice solid heatsink and no fan.
  3. gettons

    gettons LI Guru Member

    Ok , I'll use only one fan, 80x80x10mm with heatsink and with a new power adaptor ( 1500mA ) , so I can add one more fan after if I reall need it.

    Any other advices is welcome.
  4. tekunix

    tekunix LI Guru Member

    Honestly... one fan is more than enough... specially if you already have a heatsink...

    Get your own brand new WRT54GL w/
    SD/MMC Mod @
  5. sutil

    sutil LI Guru Member

    can anyone show how its done
  6. alkizmo

    alkizmo LI Guru Member

    This is my router. It's a bit overdone and uglified, but since I was already adding one fan, I decided to add two + individual potentiometers. My router is overclocked at 275mhz and most of the time, the fans are off (noise issue). So passive cooling should do the trick....

    oh right, I got a heatsink covering the ram + CPU. You dont see it as it's under the top grill.

  7. vincentfox

    vincentfox Network Guru Member

    The popularity of this mod baffles me.

    The total power draw of a WRT54GL is about 5 Watts. For the entire system!

    I have over a dozen GL units inside sealed enclosures in full sunlight in the Atlanta summers, not one of them has had any heat-related failures. I stick a small aluminum heatsink on the main chip cause hey I have them handy and it's cheap insurance.

    I can't imagine why anyone would feel the need for fan-cooling a GL unit, are you operating these things overclocked by 500% or something? What's next liquid nitrogen?
  8. leenar

    leenar LI Guru Member

    I totally agree. In fact, I haven't measured the effect of overclocking but I can tell you that Tx power setting has no effect on power consumption. Therefore I'm very sceptical that it's necessary to force cool WRT54G with increased power level. At 12V my GL draws about 240mA (which is about 3W).

    Now, I wanted to feel young again so I did a fan mod using a single 1"x1" fan. It came out pretty nice. I have a noob tutorial on how to take the router apart and install a fan at:

    There is a bunch of other "usefull" stuff. LIke a solar power project for WRT54G, WiFi antenna projects and some Bufallo WHR-G125 stuff.

  9. Toastman

    Toastman Super Moderator Staff Member Member

    For those people who are mistakenly under the impression that the power output of the WRT54 series must not be raised or the thing will suddenly explode, melt, or otherwise expire. I can tell you that running the things at 251mW will not make the transmit chip noticeably hotter. I've measured it. It doesn't.

    So why aren't you advised to up the power? It has nothing to do with heat dissipation. The power amplifier has to operate in a LINEAR mode, which it accomplishes by running well within rated parameters. If the power is raised by overdriving the amplifier, a point will be reached when it becomes nonlinear, and distorts the signal which is fed to it. In my experience (checking with a spectrum analyser) this is commonly reached when the (approximate) power level indicated by typical third party software is around 65-80mW. Some can be driven up to 120mW and still maintain linearity reasonably well. 250mW is just asking for trouble. If overdriven into nonlinear operation, the bandwidth and cleanliness of the transmission begins to suffer, both degrading performance, and creating interference to other users. You don't actually gain anything.

    I concur with the guys who think adding fans and suchlike is really a waste of time. A heatsink is nice insurance, but even that isn't really necessary. And there's no point in using a 1.5 Amp power supply, the whole thing draws only a quarter of an amp.

    I love the comment about liquid nitrogen .... nice one

  10. CaNsA

    CaNsA Network Guru Member

    Agreed Toast.

    I have been running my WRT @ 251mW for over 2years now with no probs *touchwood*

    My AG241 adsl modem is another story. Gets very very hot even with stock firmware on it. i have had to remove the face sticker from the case, stick some heatsinks int here and a fan sucking air out. All is good now though :D

    my 2p

  11. sassygirl

    sassygirl Addicted to LI Member

    this great, i am having trouble about my my fans..they are a bit noisy..hahaha..maybe i could get idea from you..thanks!:clap2:
  12. CaNsA

    CaNsA Network Guru Member

    Found a pic of my mod.
    This was before I fully removed the sticker on the front


    The internal fan was powered from a spare 6v adapter. Works well.

  13. jersully

    jersully LI Guru Member

    So water cooling is right out?
  14. Toastman

    Toastman Super Moderator Staff Member Member

    I think it's just that people feel the need to do something to brighten up their lives a little. Take me - for instance. Sitting here minding my own business, suddenly the walls started to shake, a plant pot vibrated itself off the shelf and smashed on the floor. My head began to ache. Looking out the front door of my apartment, I see a modded pickup containing, no doubt, at least a megawatt or two of amplifiers and loudspeakers, about 300 meters away. Probably on it's way to the local hospital....

    It's possible to overdo things a little....:biggrin:

    CaNsA - I think a rat has chewed a hole in the top of your router ...
  15. CaNsA

    CaNsA Network Guru Member

    2am + boredom + pocket knife = messy :D

    works a charm though, i suppose i could always plonk a grid on there to "tidy" it up somewhat
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice