Ref PO3-640-UR11 – anyone here performed a multimeter check of the PSU cable’s 6-pin connector?

LJC_202212
LJC_202212 Member Posts: 26

Tinkerer
in Predator Desktops

Such a test would verify to the community the voltage/pinout from the OEM PSU at the "ATX 6-pin power connector". The test would answer whether this is an ATX12VO standard or an Acer proprietary standard?

Answers

  • StevenGen
    StevenGen ACE Posts: 12,174 Trailblazer
    https://community.acer.com/en/discussion/676622/ref-po3-640-ur11-anyone-here-performed-a-multimeter-check-of-the-psu-cable-s-6-pin-connector

    Btw, you have posted at least 4-5 posts on the same question, the PO3-640 does not quote voltage/pinout from the OEM PSU and doing and testing this is dangerous for a normal user to do, we do not encouraged any user to do any livee power tests, as they are very dangerous and should only be done by an experience technician,, as a normal user can electrocute himself and also damage the PSU or the desktop motherboard.

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  • LJC_202212
    LJC_202212 Member Posts: 26

    Tinkerer

    :-) I'm looking at your post and a post from one of my other questions, where I see for the first time a pinout for the 6-pin ATX power connector - getting closer to the complete information I seek:

    1) Your diagram confirms that pin#1 uses the PS_ON standby signal. although not stated - since the LITEON PA-4501-1AC PSU only pushes 12VDC, I can assume with confidence that pin#1 uses 12Vsb for the standby signal.

    2) The diagram's pinout shows a ground on pin#4, however my actual layout does not have a wire going to pin #4 (unused).

    The information from 1 and 2 above seems to conflict with the ATX12VO (12V Only) Desktop Power Supply Design Guide, Rev002 dated May 2020. It this guide, pp32, paragraph 4.2.2.2 and table 4-3 shows:

    1) The connector is the same form factor as the PCIe 6-pin connector (the root of confusion for some).

    2) The 6-pin connector (also called the "Extra Board" connector) is in addition to the 10-pin Main Board Connector (not used by the PO3-640-UR11). The purpose of the 6-pin Extra Board connector (shown in your above graphic and picture as "ATX_Power") is to provide an additional 216-288 watts of power above that provided by the 10-pin connector. The Extra Board power is likely, primarily for the MOBO circuitry used to convert 12VDC to 3.3VDC and 5VDC used by the MOBO and by the SATA connector for peripherals.

    3) Table 4-3 shows the ATX12VO pinout for this connector as +12V1 on pins #1, 2, and 3 with ground on pins #4, 5, and 6, which is different than the pinout diagram you posted above.

    4) Acer is using an ATX12VO PSU, but non-standard connector/pinout scheme (i.e., does not use a 10-pin Main Board connector and uses a non-standard 6-pin Extra Power (ATX_Power) connector with ATX12VO elements but non-standard pinout).

    Conclusion (please confirm if you are allowed/able] - Acer is using a non-standard ATX_Power scheme/pinout. This information is useful to make an adapter: 24-pin to 6-pin, 20-pin to 6-pin, or 10-pin to 6-pin, thus, increasing the potential pool of replacement/upgradeable ATX12VO PSUs in the future.

    BTW: Table 4-4 of the design guide confirms/agrees with your above ATX_12V1 and 12V2 pinout diagram - confirming this connector scheme is a ATX12VO standard.

  • billsey
    billsey ACE Posts: 34,246 Trailblazer
    edited December 2022

    It looks like you posted essentially the same question in a bunch of different threads. I posted pinouts for you on a few of your other threads. It's more efficient and less confusing for people to to only ask the questions once and wait for an answer instead of over and over again...

    Click on "Like" if you find my answer useful or click on "Yes" if it answers your question.
  • Wado_Vice2137
    Wado_Vice2137 Member Posts: 1 New User
    edited February 3

    Hi,

    looks like the thread is dead for over a year, but it's the first one to pop-up after searching the MOBO or PSU numbers in google.

    I have the Acer Nitro N50-640 PC with B66H6-AD Motherboard and OEM Lite-On 550W PSU.

    I'm trying to upgrade the GPU, however the stock PSU lacks the necessary connectors, plus it's only 550W rated (I don't know how Acer was able to pull this off, 550W PSU powers a RTX3060 and i7-12700k (?) ).

    I did measure the voltages on the 6-Pin ATX power connector and can confirm the diagram posted by @StevenGen is correct. There are two +12V DC lanes, a PSU_ON on pin#1 and TWO grounds (Pin#4 is unpopulated).

    HOWEVER: I re-pinned the connectors and took +12V DC from the PCIe lane. The PC won't start when connected this way. It works fine when one of the +12V is taken from the original ATX_POWER 6-pin loom (doesn't matter which one). The ground cables can be taken either from the PCIe loom or the ATX_POWER. It even works when one of the 12V DC power is from the PCIe loom an the second one from the ATX_POWER connector. As soon both +12V lanes are connected to the PCIe lane the PC won't boot.

    I was hoping that I will be able to make a custom connector by re-pinning a standard ATX 3.0 PSU's 10-pin connector. I used the below pinout schematic for the 24PIN Motherboard connector:

    Fu6MlWq.jpeg

    But of course this doesn't work. The PC won't boot.

    Any ideas why? I mean, the weirdest thing for me is why it doesn't start, when the 12V is taken from the OEM's PSU PCIe's lane. Like somehow the MOBO and PSU has to be connected by the ATX_POWER connector at least by one +12V cable in order for the[Sensitive Content] thing to power up.

    [Edited the thread to hide sensitive content]

  • billsey
    billsey ACE Posts: 34,246 Trailblazer

    Some power supplies require a load on one of the Vcc lines in order to work. Needless to say in a 12VO system there isn't a load on any 5V line. Some 12VO systems seem to use the matching ground for the PS_On line as a sense (power good in your diagram) and they act weird when the wire isn't connected. Acer just shares that ground with the 12V return grounds, but your PSU might need to have it connected. Try putting a ground into that socket on the connector.

    Click on "Like" if you find my answer useful or click on "Yes" if it answers your question.

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