Page 1 of 2 12 LastLast
Results 1 to 10 of 11

Thread: 4 pin ATX to female USB

  1. #1
    Newbie
    Join Date
    Sep 2009
    Location
    NoVA
    Posts
    22

    4 pin ATX to female USB

    Does anyone know of a harness that has a 4 pin ATX connector on one end, and a female USB port on the other? I have spent a good deal of time trying to find one, and the closest I can find is a 4 pin molex to USB. While I can probably get a 4 pin ATX to 4 pin Molex converter (see below), I would prefer to just find a 4 pin ATX to female USB.



    I realize I can solder my own female USB port onto a 4 pin ATX lead, but my soldering skills on wires that small are pretty poor, so I am hoping to find something pre-made.

    Thanks.

  2. #2
    Confusion Master
    Auto Apps:loading...
    Enforcer's Avatar
    Join Date
    Sep 2003
    Location
    If you go down to the woods today, You're sure of
    Posts
    14,618
    I don't think you'll find one.

    It could be pretty dangerous.

    a 4 pin ATX cable will normally carry 12v whereas USB is 5v.

  3. #3
    Newbie
    Join Date
    Dec 2011
    Posts
    20
    You want the red line (missing from that cable), the red line is 5V.

  4. #4
    Neither darque nor pervert DarquePervert's Avatar
    Join Date
    Apr 2004
    Location
    Elsewhere
    Posts
    13,949
    Quote Originally Posted by wprime View Post
    You want the red line (missing from that cable), the red line is 5V.
    There is no red wire in that connection because that connection provides +12v to the motherboard.
    You're thinking of a HD connector, also called a molex connector (which is stupid, since Molex is just a brand name).
    Have you looked in the FAQ yet?
    How about the Wiki?



    Under normal circumstances, a signature would go here.

  5. #5
    Newbie
    Join Date
    Dec 2011
    Posts
    20
    Quote Originally Posted by DarquePervert View Post
    There is no red wire in that connection because that connection provides +12v to the motherboard.
    You're thinking of a HD connector, also called a molex connector (which is stupid, since Molex is just a brand name).
    Yes but that's what he needs. Wiring 12V into USB is asking for trouble.

  6. #6
    Maximum Bitrate
    Join Date
    May 2012
    Location
    Grandville, MI
    Posts
    566
    A little more expansion on this...

    USB is 5 volts...

    The Drive power connector as shown has 2 blacks, a yellow and a red.
    The Yellow is 12 volts and the red is 5 volts. For most drives the 5 volts powers the electronics and the 12 volts powers the mechanism.

    The ATX connector to your motherboard requires 12volts.

    Also, USB does not ALWAYS product 5volt but only once the system turns the USB port on. Some machines have "always on" usb ports to allow charging of devices.

    You want to use the same power supply that your motherboard is using to power your ATX connector thus the connector you point out is the only one you want to use.

    You don't say what you want to use this for but I am assuming you are trying to use a USB port for powering your CPU and since your CPU controls the USB port this is a very bad idea. And if you are looking to use USB because you have many of those ports and very few of the older style drive power connectors you need a Y adapter.

    For my motherboard I only had 1 of these older 4 pin connectors. My case came with an external plug with 3 wires to go out. I decided having a remote turn on, a ground and a +5 volt supply to the outside would be a nice feature. I also needed the 12volts to go to my ATX connector. My power supply only had a 20 pin connector but this should work find on the 24pin board because I don't use the PCIe slot at all. But it is essential that the CPU connector is powered.

    I took a Y connector and cut off one of the connectors. I then took the yellow and black wires from the CPU power connector and spliced them to the yellow and one of the black wires from the Y connector. I then took the red connector and the other black connector and provided them along with the remote turn on lead from the M3-ATX power supply to the external cable.

    My computer has worked without issue since doing this modification and plugging in the connector to the CPU power connector.

  7. #7
    Newbie
    Join Date
    Sep 2009
    Location
    NoVA
    Posts
    22
    Quote Originally Posted by redheadedrod
    You don't say what you want to use this for but I am assuming you are trying to use a USB port for powering your CPU and since your CPU controls the USB port this is a very bad idea. And if you are looking to use USB because you have many of those ports and very few of the older style drive power connectors you need a Y adapter.
    The reason I was asking is that I have ordered a DCDC-USB, and plan to use that to charge a Nexus 7 / power a USB hub. Since researching it some more though, I don't think that I will need the ATX to USB, I have this USB hub which accepts a Molex connector on the back to turn it into a powered hub. Am I correct in that I can simply take the output from the DCDC-USB, using a cable like I posted in my original post, plug that into the Molex on the back of the USB hub and then plug my Nexus into the hub for charging?

    Based on that, does anyone also know where I can get one of these:

    http://www.altex.com/4-Pin-Molex-Con...Fcyj4AodvWMAUg

    That place has the cable listed for $2.19, not bad, happy to pay that price. But the shipping is almost $16!!!!!!!!!!!!! Crazy.
    Last edited by naiku; 05-17-2013 at 07:27 PM.

  8. #8
    Maximum Bitrate
    Join Date
    May 2012
    Location
    Grandville, MI
    Posts
    566
    That is just a floppy drive power connector adapter. Should be readily available in a lot of places.

    The hub you are buying has a USB to 5v wire. If you cut this apart you can just wire the power plug directly to your power supply. You just have to make sure you know which wire does which.

    You COULD plug the nexus into this USB hub for charging but depends on what you will be using the nexus 7 for. You might be better off making a socket from your DCDC unit with a cable to run to your tablet for just the power. Would be a simple matter to get an old USB socket that attaches to a back plate on a computer case. This will actually have 2 USB ports on it. You could then wire those directly to your DCDC power supply and charge any 2 devices. And mount the sockets anywhere you want.

    The power wires to use for these should be simple to find with a simple google search.

    Total cost to do this mod the way I mention it would be very minimal since a USB backplate is very cheap and very readily available.

    In the future you might be best served to post what you are trying to do and ask for suggestions how to best accomplish it.
    Last edited by redheadedrod; 05-18-2013 at 08:14 AM.

  9. #9
    Newbie
    Join Date
    Sep 2009
    Location
    NoVA
    Posts
    22
    redheadedrod, thanks for the info. I ended up finding one of those floppy power connectors on eBay cheap enough, so went ahead and ordered that one. The reason I am looking at the molex/ATX/FDD power cables is because I am trying to see how much of this can be almost entirely plug n play, instead of having to do any soldering.

    I actually have 99.9% of this already working, but am currently using one of these for providing power. I soldered 2 female USB ports onto the output leads, and plug the Nexus into one for charging, and the USB hubs power cable into the other. While it works fine, it does not provide particularly reliable power. On a 90 minute commute, with my Nexus just playing music from a USB flash drive, GPS, Bluetooth, Wireless etc. all off, I am lucky if it charges at all. A user on another forum I read has a similar set up, but using the DCDC-USB to provide power and his battery charges quickly.

    The Nexus has replaced the OEM head unit in my car, I use it for playing music, navigation, etc. Along with the Nexus I am using a Joycon EXR for steering wheel controls, along with that being plugged into the USB hub, there is also a Sabre USB-DAC (sends a signal to a JBL MS8) and a 64GB Sandisk flash drive. All working well, but occasionally the flash drive does not get picked up, and I typically lose a charge. Hoping the DCDC-USB remedies this, and also feel it should last longer than the eBay converter I posted above.

    Thanks again.

  10. #10
    Maximum Bitrate
    Join Date
    May 2012
    Location
    Grandville, MI
    Posts
    566
    Ok, sounds like you were trying to make more work for your self than you needed then.

    The DC-DC should work since it is a high quality unit that provides more than enough power for you.

    I would just rewire the sockets you currently have to the DC-DC unit. I am assuming it comes with its own wires so it should be similar to hookup.

    Those cheap setups like that one you listed generally don't work the best. You MAY get lucky but 3A really is not that much when you are trying to power a USB hub that potentially could use up almost the whole 3A by its self. (Typical USB ports only provide up to 500ma but if you are using a powered hub with 4 ports I would assume that would be up to 4x500ma or 2A. ) And I dare to bet if you look at the power supply that charges your Nexus you are going to be using a little power as well. Probably more than the 500ma that a standard USB port can put out. I believe that if you try to charge a phone, tablet or other device through a typical USB device it is limited to the 500ma but if you are using one of the dedicated charge supplies they can provide more. (The generic ones provided for our phones here at work provide 1A.)

    It is likely you were pushing this cheap Chinese unit beyond its max...

    Rodney

Page 1 of 2 12 LastLast

Similar Threads

  1. Building specific 40 pin TFT LVDS female cable to 20 pin JAE Female CON
    By JacquesB in forum General Hardware Discussion
    Replies: 7
    Last Post: 08-13-2010, 10:39 AM
  2. USB to Phono with Female-Female USB Adapter
    By mpman in forum Car Audio
    Replies: 12
    Last Post: 04-21-2010, 08:07 PM
  3. female??
    By erazor in forum Off Topic
    Replies: 135
    Last Post: 01-02-2010, 11:05 AM
  4. someone tell me why im a female
    By rockthevolvo in forum Off Topic
    Replies: 27
    Last Post: 01-26-2005, 08:59 PM
  5. Any female mp3car members?
    By carabuser in forum Off Topic
    Replies: 13
    Last Post: 12-21-2004, 02:46 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •