1. Welcome Guest! In order to create a new topic or reply to an existing one, you must register first. It is easy and free. Click here to sign up now!.
    Dismiss Notice

slowing a fan down

Discussion in 'Miscellaneous Hardware' started by doug brown, Feb 9, 2016.

  1. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    Hey guys is me again and i'm back with a question to help finish another cosmetic project i have.
    i have a small fan that i want to slow way down. it's connected to a 5v power source so can i use resistors to slow it down to a slow spin.
    The project i'm finishing is the original xbox spinning jewel mod. i did this a few years ago and now i'm looking to get it done. IMO the jewel spins way to fast. thanks for any advise guys.
     
  2. donetao

    donetao Banned

    Joined:
    Jan 31, 2015
    Messages:
    905
    Operating System:
    Windows 10
    Hi Doug! You'll get some great answers here on CHF about this question. This is a free program I have but I've never messed with the fan speed .

    Here's a good link. There are no PUP's here.;)
    http://filehippo.com/download_speedfan/
     
  3. DSTM (Dougie)

    DSTM (Dougie) Registered Members

    Joined:
    May 3, 2009
    Messages:
    8,270
    Location:
    SYDNEY AUSTRALIA
    Operating System:
    Windows 7
    Hi Doug. Yes you can use resistors to drop the voltage and slow the Fan down.
    Any electronics shop will advise you what size and how many resistors you will need to atain what rpm your aiming for.
     
  4. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    Thanks for the link donetao but i don't think i can use it. the fan is just connected to a 5v source so the og xbox don't know it's there. i just need a way to lessen the power to the fan to slow it down. that's why i thought a resistor would work.
     
  5. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    OK thanks DSTM.
     
  6. donetao

    donetao Banned

    Joined:
    Jan 31, 2015
    Messages:
    905
    Operating System:
    Windows 10
    Your welcome. I told you that you would get some more answers.;);)
     
  7. GimboV

    GimboV Registered Members

    Joined:
    Mar 9, 2014
    Messages:
    161
    Location:
    Illinois
    Operating System:
    Windows 8
    Computer Brand or Motherboard:
    Asus X99 Deluxe
    CPU:
    I7 5930K oc'd to 4.4ghz
    Memory:
    16GB Corsair Vengeance 2800mhz
    Hard Drive:
    Samsung 850 pro 256GB Seagate Hybrid 2TB
    Graphics Card:
    EVGA Nvidia 970 4GB GDDR5
    Power Supply:
    Corsair HX1000I
    I am unsure what type of fan you are using but if it is designed to run on twelve volts, at voltage lower then 5 volts it may not run or start. Most 12 volt fans require around 7 volts just to start.
     
  8. bassfisher6522

    bassfisher6522 Registered Members

    Joined:
    Jan 24, 2016
    Messages:
    365
    Operating System:
    Windows 10
    If this was a PC I would suggest a fan controller....but since this is an Xbox mod.....I'm clueless.
     
  9. Rich M

    Rich M Guest

    Joined:
    Dec 24, 2013
    Messages:
    4,580
    Location:
    NE Pa USA
    Operating System:
    Windows 7
    Computer Brand or Motherboard:
    MSI Z97 PC Mate LGA 1150 Intel Z97
    CPU:
    Intel i7 4790K 4.0Ghz
    Memory:
    Corsair Vengeance 16GB (2x8GB) DDR3 2133
    Hard Drive:
    Crucial 256 Gb SSD+ WD Raptor 300 Gb Sata III
    Graphics Card:
    Radeon R9 280 2GB HDMI
    Power Supply:
    Seasonic 750 watt
    Yeah that is my problem too.
     
  10. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    the fan is a small fan like on top of a heat sink. similar to a fan from a radio controlled ESC but a little bigger. the fan has been hooked up and working for a couple years so it does work. i just want to slow it down. it's hooked to the 5v power going to the HDD. i'm not sure how to link my YT channel but if you google modded xbox spinning jewel mod my original xbox with mod chip and blue lights should be the first in the search.
     
  11. bassfisher6522

    bassfisher6522 Registered Members

    Joined:
    Jan 24, 2016
    Messages:
    365
    Operating System:
    Windows 10
    I found that when I googled it before your last post. BTW, that's pretty darn cool. Have you taken the housing apart and looked at the PCB (mobo) and see if there is a fan header of any kind or an open header of any kind?

    With the Xbox open....take some good, clear pictures of the PCB (mobo) and we'll take a look at it and go from there. There maybe some sort of splitter you could use off of that power source you're using now to connect a fan or another source if available.
     
  12. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    Thanks bassfisher6522. yeah i had it and a few other og xbox's open there is a fan header and it's controlled by the xbox. more so when it's soft or hard modded. the fan that was in it on the video was replaced with a slightly larger blue led fan so it may use more power than the stock one.
    I'll take some time later and open it up to snap a few pics. just don't laugh i think i used hot glue to cover the splice in the wires instead of tape or shrink tube. that's what i had to use when i did it.
     
  13. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    OK guys i opened it up and snapped a few pics.
    fa56a2a1165fb7172c0220df5b7c6853.jpg
    594d53ae7cf622af4e2bcff6c374559a.jpg
    first pic is it open and the HDD and DVD drive removed. second pic is where the fan connects. i can control the fan speed but i don't want to connect the spinning jewel there because the xbox might over heat if the fan speed is set low.

    this is the fan i used it is 12v but i hooked it up to the 5v to slow it down but it's not slow enough.
    d133267a08c003dfd5958bf31cedc57a.jpg
    i have a few resistor, 220 and 180 from doing head lights and tail lights is my RC's but i'm not sure if it will do what i want in this situation.
     
  14. Aus_Karlos

    Aus_Karlos Registered Members

    Joined:
    Jan 24, 2016
    Messages:
    32
    Location:
    Australia, WA - Perth
    Operating System:
    Windows 10
    Computer Brand or Motherboard:
    ASUS Z97-A
    CPU:
    i7 4790K @4.4ghz
    Memory:
    16GB (4x4gb) G.Skill Ripjaw @ 1600mhz
    Hard Drive:
    3x Samsung 850 EVO 500gb (RAID0 - Games) 1x OCZ Agillity 3 128GB (OS) 1x 2TB WD Green (Backup)
    Graphics Card:
    2x EVGA GTX980Ti 6GB SC (1420mhz/7090mhz)
    Power Supply:
    Corsiar AX1200i
    To drop a 12v fan down to a low rpm you can do the following calculations to pick the correct resistor.
    Ohm's Law
    V-IR (Voltage = Current x Resistance)
    Your fan has a current rating of 0.08A (I=W / V) Current = Watts / Volts
    Now we work out the Fans internal resistance using Ohms Law still.
    R=V/I = 144.57 Ohms

    Now if you want to drop it to 5V we need to work out what the current draw should be to find the right resistor. Then use the difference in voltage along with the reduced current to work out the resistor needed.
    I=V/R = 0.0345A (I= 5/144.57)
    Difference is 7V (12-5=7)
    R=V/I = 202.89 Ohms (R = 7/0.0345)
    So to reduce your fan speed to over half you need a Resistor with more than 202.89 Omhs, However do note that some fans will stop spinning at a certain voltage and some even switch off if the RPM is too low. Most non-controlled fans that have a rpm range of 1000 will turn off at about 400rpm, where as the 4pin PWR fans can run as low as 200rpm (Of the same Spec).
     
    bassfisher6522 likes this.
  15. bassfisher6522

    bassfisher6522 Registered Members

    Joined:
    Jan 24, 2016
    Messages:
    365
    Operating System:
    Windows 10
    Damn....MS is still using ribbon cables....WOW!
     
  16. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    i just wanted to jump in and say this isn't a new xbox. it's the old first xbox MS made. well version 2. it's not v1 because the controller ports connect to the mobo. the very first version has a daughter board they connect to then the mobo.
     
  17. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    i had a thought. how about a potentiometer. i have a few from some servos that i stripped the gears in. i could mount it in the back of the xbox and control the speed that way. i was thinking if i used a resistor that lowered it to much then it wouldn't spin when i powered it on but if after it was on i could slow it down to a crawl. would that work out or am i going the wrong way with this?
     
  18. Tony D

    Tony D Super-Moderator Super Moderators

    Joined:
    Sep 25, 2009
    Messages:
    3,441
    Location:
    SE Pennsylvania, USA
    Operating System:
    Windows XP Professional
    We haven't talked about the power rating of your drop down resister. We're looking at 80mA and 7 volts. That works out to be 560 mW or just over 1/2 Watt. You'll need a resistor or pot capable of that wattage. Well, that's if I remember my Ohm's law and power calculations correctly.
     
  19. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    OK i'll dig through my spare parts hoard and see what i come up with. thanks again for all the help. i like this forum. you guys are the most helpful i found so far. a lot of forums assume every one should know every thing or don't even respond to a post but you guys are great.
     
  20. doug brown

    doug brown Registered Members

    Joined:
    Dec 8, 2015
    Messages:
    107
    Operating System:
    Windows Vista Home Premium
    just reporting back on this project.
    i used a 1/4 watt 220 ohm resistor and it slowed it down some. it's not as fast as it was so i'm ok with it for now.
    when i can i'll get the one you suggested Tony D and swap it out.
     

Share This Page