power supply - How to draw 12W DC output from PC motherboard/PSU/USB?

08
2014-07
  • SNag

    I recently bought a Dell AX510 Soundbar speaker that fits snugly under my monitor.

    dell ax510 soundbar

    However, my monitor, Dell IN2030M is a budget model, and while it does have the plastic grooves to fit the soundbar, it is missing the port where I could plug in the power connector from the speaker.

    The speakers use a standard DC power connector requiring 12W.

    dell ax510 dc power connector

    I have the option to use an external power adapter like this, but what I'm interested in learning is if there is a way to pass the required 12W power to the speaker from the motherboard using a cable convertor, such as a USB to DC, or a PCI to DC, or directly from the PSU etc. Is there a way?

    Update: I have this information from the speaker manual:

    • Power requirements: DC 12V +/-5%, 1.0 A
    • Total power output: 10 Watts continuous average power
    • Answers
  • nixda

    The 4-Pin peripheral connector of your PSU delivers 12V DC. If you buy the correct cables and adapters, you should be able to connect your soundbar to it.

    All together it shouldn't cost you more than 10$

    1. Here we see the cable tree of your PSU CoolerMaster Thunder 500W together with a peripheral (Molex) connector

      enter image description here enter image description here

    2. A 12v 4-pin molex to 5.5mm x 2.1mm power adapter cable costs ~5$.
      Don't be confused by the red+black cable colors.
      Those two used pins are the correct ones for +12V DC

      enter image description here

    3. The key is to find the correct connector diameter.
      According to this description it's a 5.5mm x 2.1mm barrel connector female

      enter image description here enter image description here

    4. At this point, we need a coupler since both ends (soundbar DC cable + Molex adapter cable) are male. A female-female gender-changer coupler again costs ~5$. (or $0.80)

      enter image description here

    5. Surely you will need an Extension Cable which costs ~2$. Despite this, you have to find a small hole to fiddle the cable out of your PC tower and up to your monitor.

      enter image description here


    • Related Question

    power supply - What does a recommended PSU from motherboard include?
  • R4D4

    I'm looking at getting an Asus P5G41T-M LX G41 motherboard. In the manual here, it states that a minimum of 400 watt PSU is recommended. My question is, what is this figure including as I can't quite see the motherboard alone requiring 400 watts?

    Thanks.


    • Related Answers
  • paradroid

    Everything else that makes up the machine, obviously: the CPU, discrete graphics card (which can often use a lot, if fitted), RAM, disk drives, optical drives, PCIe cards, case fans, etc.

    Also, the figure would be for full maximum load (plus some extra capacity over that), and not just what the computer will usually be using while idling.

    There are quite a few online calculators which you could use to see how much each component roughly uses, like this one.

    It would be wise to get a good quality PSU with a high efficiency and not to get one much more powerful than you need, as it would be a waste of money, and slightly less efficient. PSUs are generally most efficient at 40-70% load (roughly).

    enter image description here

  • ppumkin

    That is just a general minimum rating needed for a maximum setup (all hard rives and peripherals installed) but it excludes the power ration for graphics cards, s o...

    One thing to consider is not just the motherboard, but if you want to get a good graphics card-- that one alone needs 400Watt + 400Watt Motherboard .. So many gaming PC's use 850Watt power supplies. (you will notice when you buy a high end GFX card they suggest using 600/800/1000Watt and this is the max for everything used)

    It does not meaning uses the 850Watts constantly, it is a switched power supply and is controlled via the motherboard and/or software of your operating system. That is why it is important to enable power saving features and install the correct drivers for your OS.

    So when you are not doing anything it can use as little as 50Watts.

    But when gaming it jumps up to 600-800watts.

    One thing to keep in mind- do not buy the cheapest pwoer supplies- because they tend to blow out when you start using the near maximum rating. I have seen this happen dozens of times, and people come back later and buy a proper PSU(you can tell by comparing the weight of the same rated PSU) The better PSU's sue high quality capicitors and coil transformers and a bit more clever technology to decrease the chance of a blow out, they also usaully come with 3 to 5 years warranty, where as chinese el-cheepo only 1 year.

    Usually when i am in doubt i use one of these wall power meters and monitor the usage.

    enter image description here