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Other Can you hook up LEDs to a mobo fan header?

Discussion in 'Hardware' started by ModSquid, 23 Oct 2015.

  1. ModSquid

    ModSquid Modder

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    Yo!

    As the title suggests, I was hoping to hook up a string of LEDs to a spare fan header on the motherboard, using a spare fan plug I could wire up. Is this possible or a bit daft?

    I know they must be 12v fan headers but I also know the square root of nothing about electronics, other than that you have to take current and such like into consideration.

    Am I about to ruin things/create a hazard by doing this? Shall I just get some molex plugs and use those?
     
  2. noizdaemon666

    noizdaemon666 I'm Od, Therefore I Pwn

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    Personally I'd go for molex, but there isn't an reason a fan header wouldn't work, just set it to always on/max powah in BIOS
     
  3. Digerati

    Digerati Minimodder

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    I would not even try a motherboard fan header. On many motherboards, they are monitored for fan speeds by the chipset and of course, LEDs don't spin. If this was really necessary, I would use a direct connection from the power supply. That said, do you spend your time gazing into your computer, or watching your monitor? ;) If you really want to add fancy lighting (which do nothing for performance, consume some power, add some heat and do nothing for performance - worth repeating), I recommend adding some LED case fans.
     
  4. Nexxo

    Nexxo * Prefab Sprout – The King of Rock 'n' Roll

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    LEDs really consume negligible power and generate no heat. But less tends to be more in aesthetic terms.
     
  5. Digerati

    Digerati Minimodder

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    I agree they consume very little, but they do consume and while the LEDs do not themselves radiate heat like a regular lightbulb does, the PSU and regulator circuits supplying them power generate more heat just to power them - again, hardly any but my tongue-in-cheek remark was to illustrate they do nothing for performance and the "action" if you will, is happening on our monitors, not inside our cases. It is my experience that once the novelty of fancy lights wear off (which does not take very long, typically a day or two - no one cares about lights inside the case anyway.
     
  6. David

    David μoʍ ɼouმ qᴉq λon ƨbԍuq ϝʁλᴉuმ ϝo ʁԍɑq ϝμᴉƨ

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    That is true of any case lighting, so it's a redundant observation, IMO.
    Are you on the right forum? :duh:
    Again - PC enthusiast forum, matey. :thumb:
    Silly statement is silly.
     
  7. ModSquid

    ModSquid Modder

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    Well, I was going to wire them up to practice my soldering and because I was a bit disappointed with the UV cathodes I bought. I thought they'd be brighter. Plus the LEDs were originally bought for another project in which they will be on prominent display, so practice will be ideal.

    I can see both sides in this argument, actually. I do agree they add little in terms of value, but then Spreadie's point holds very true - almost everything members do on here could be argued as a waste of time in that case! Consider this - instead of Mod of the Month, we'd end up with three pages on Best Value Shop-Bought Black Box of the Month or similar.

    I was also going to see if I could make my own LED fans with the Corsair ones I have, especially since the ones on sale now (with the possible exception of the new Riings) are all fairly naff and just point four beams into the fan blades. The Corsairs have these curious holes on the rim that I'm sure could be drilled out...

    As far as fan speed and non-spinning LEDs go, I was of the impression that fan speed reported by motherboards was because they knew how much voltage/power/PWMs (I just made that up) they were sending TO the fan, not what was being reported FROM the fan.

    Otherwise, why would my CPU fan currently report as spinning at 2200rpm when the header is in fact powering the H80i pump and no fans?
     
  8. noizdaemon666

    noizdaemon666 I'm Od, Therefore I Pwn

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    The third pin on a three pin fan header is for the tachometer, so yes it does measure fan speed. Your pump is spinning at 2200RPM.

    However, that's off topic lol
     
  9. Digerati

    Digerati Minimodder

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    You took it out of context. I said, "It is my experience that once the novelty ... wear off ...".

    Yes, I am in the right forum. It is just my personal feeling that power/performance matters most. As for aesthetics, I prefer a conservative, "sleeper" look that then blows the socks off everyone when the rubber meets the road.

    But I do appreciate when a lot of effort goes into pure aesthetics too - when professionally done. But the image I get when hearing about "hooking up a string of LEDs" just does not "sound" too professional to me. No offense meant then or now. I'm just saying, it's what happens on the monitor(s) that really counts.
     
  10. The_Crapman

    The_Crapman Don't phone it's just for fun. Staff

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    I still love to to gaze over at my nicely lit up case and all the sparkly goodness inside and after 6 months. If you didn't want to look at it and let other bask upon it's glory, you wouldn't get a case with a window in the first place. And what better way to accentuate that with some case lighting.
     
  11. Digerati

    Digerati Minimodder

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    Well, now I disagree with that completely. I love cases with a side window because I can easily look inside without having to remove the side panel to make sure the fans are all spinning and I don't have a layer of heat trapping dust building up. This is especially nice with my primary computer as it slides into a slot in my desk. I can just slide it out about 6 inches and see inside. Without a side panel window, I would have to pull the case all the way out of the desk to remove the cover.

    So you use the window to gaze at sparkly goodness, I use the windows for inspections. I see value in both.

    Now I am not saying the interior should not look good. I pride myself on keeping the interior "tidy" through good cable management, component layout, and dust control. But I see the primary reason for that is heat control by minimizing interfering with the air flow through the case. But it is also dotting the I's and crossing the T's for a more professional looking build too.
     
  12. The_Crapman

    The_Crapman Don't phone it's just for fun. Staff

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    If you had some case lighting it would be even easier to see if they were all spinning and how much dust there was. :D
     
  13. theshadow2001

    theshadow2001 [DELETE] means [DELETE]

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    No, it should be fine.
     
  14. Digerati

    Digerati Minimodder

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    Perhaps - if white. But I have no problem seeing into the case interior through the window, so no big deal, for me.

    I would still go directly through the PSU to power these LEDs, however. Easier, IMO, to hide the cables, and there is no worry about the chipset attempting to control the speed (voltage) that way either.
     
  15. jinq-sea

    jinq-sea 'write that down in your copy book' Super Moderator

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    I've mentioned this before - you're rubbing enthusiasts up the wrong way again. Please stop. Thank you.
     
  16. The_Crapman

    The_Crapman Don't phone it's just for fun. Staff

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    What kind of led strip is it? I've got a phobya strip I can try in mobo fan header see how it works for you before you start soldering stuff up?
     
  17. ModSquid

    ModSquid Modder

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    I'm cross now.

    My post is missing. And the missus is raging. I'l try again tmrw
     
  18. ModSquid

    ModSquid Modder

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    Righto - I can't for the life of me remember what my other post was going to be (or how I managed to make it disappear), but I think it was along the lines of querying that third wire. Is it measuring fan speed, or driving it? That's the bit I don't quite get.

    Crapman - that would be great if you could give it a go for me. Appreciated!
     
  19. noizdaemon666

    noizdaemon666 I'm Od, Therefore I Pwn

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    It measures it as far as I know, just reports it back to BIOS. Though I could easily be wrong on that one.
     
  20. The_Crapman

    The_Crapman Don't phone it's just for fun. Staff

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    I'll plug it in tonight and let you know and upload some pics. I'm pretty sure that the phobya fan header connection only has 2 pins so if it works, you can just use those and not the 3rd.

    As far as I know, the fan reports it's speed to the mobo/controller on that 3rd pin. 3 pin fans have their speed controlled by voltage alone. 4 pin pwm fans have their speed altered through the 4th pin by some sort of pulse regulation.
     

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