motherboard - My PSU 2x2 12v connector is reversed! Why?

07
2014-07
  • kaedhen

    The 4 pin processor core voltage connector on my PSU unit won't fit into the 4 pin socket on my motherboard! The pattern of rounded and square pins on the connector is the reverse of the pattern on the motherboard socket. Why would this be the case? Is there a purpose for the reversed pins? How can I tell if a PSU will have normal or reversed pins before I buy it? My motherboard is an Intel D865GLC Socket 478 mATX w/ Video and Sound.

    • Answers
  • techie007

    I'd bet you are confusing the connectors.

    Here's a picture of what your PSU is reported to have for connectors:

    PSU connector image:

    Your (old) motherboard has a 20-pin ATX main connector, with a 2x2 ATX auxiliary connector.

    Your new PSU has a 20+4 pin ATX main connector, and a 4x2 ATX auxiliary connector (shown above as "ATX 4+4 PIN").

    You should:

    1. Detach the "+4" plug from the 20+4 main plug on the PSU, and don't use it. If you can't detach it, the 20-pin part should still fit into the 20-pin ATX main connector on the board, with 4 pins hanging over the one edge, not being used. This can happen as long as there's no components in the way (since the board was designed BEFORE 20+4 connectors existed, they may have stuck a capacitor or something in the way).

    2. Use HALF the 2x4 (ATX 4+4) plug in the ATX 2x2 connector on the board. It should fit properly, with 4 pins hanging over (not being used). It should only fit the way it's intended (they're keyed) but watch it, because you CAN jam the wrong set in if you don't pay attention and push it in hard enough.


    • Related Question

    power supply - What's the highest PSU wattage I can go for an Intel D865PERL motherboard (Pentium 4)?
  • geff_chang

    What's the highest PSU wattage I can go for an Intel D865PERL motherboard (Pentium 4)?

    I have an Intel D865PERL motherboard: http://www.intel.com/support/motherboards/desktop/d865perl/

    with the following processor: Pentium 4 CPU 2.80 GHz, 2.79 GHz, 1.00GB RAM

    I only have a 300W PSU and I clearly need more, because the video card says so.

    Is it safe for me to upgrade to a 550W PSU? (Or, what's the highest PSU I can go for?) Won't it fry my motherboard? I normally leave my machine on for months.

    Thanks.


    • Related Answers
  • phoebus

    The wattage of your power supply indicates the power load it can supply. It does not mean there is more current running through your motherboard. You can put any standard PC power supply into that system.

  • 8088

    There is no upper limit on the wattage of the power supply which your system can use other than defined by chassis physical dimensional (mechanical) requirements. A power supply will only deliver the current pulled by the system and will not "push" high current through the system.

    One thing to keep in mind is many power supplies are inefficient at a light load. For example, if you get a 1kW supply and are only pulling 250W (25% load), it could be 60-70% efficient and actually waste more power than an appropriately sized one. One way to avoid this is to get an 80 PLUS rated power supply which requires the PSU to be >= 80% at light, middle and heavy loads.

    Image from Jeff Attwood's Coding Horror: When Hardware is Free, Power is Expensive:

    alt text