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enter image description here

Would it make sense to connect the GND pins of an 8-pin PCIe power connector to a common point ground (which is at earth potential) and then plug that dummy connector into my new GFX card, before installing the GFX card onto the motherboard?

The setup would look like this. enter image description here

This way the motherboard and GFX card are at the same potential, before making contact, and while installing. After installing, when the GFX card is in place, i will remove the dummy connector and attach the real power connector from the PSU.

Good plan? Bad plan?

Edit: 1 answer suggests touching the bracket/faceplate to equalize the charges.

But, if the bracket is isolated from the GPU (and the surrounding circuits on the card), then touching the bracket won't do anything to the card. Which can be a good thing. Because you won't damage anything. But then a potential difference between the graphics card and the motherboard (on which it is supposed to be installed) may remain. That can result in an ESD event at the moment the graphics card slides into the PCIe x16 slot.

So, howto avoid ESD on a new graphics card? (Besides leaving it into the box.)

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  • \$\begingroup\$ Get an antistatic wrist band, wear it and connect it to the chassis. Don't wear fleece. \$\endgroup\$
    – winny
    Commented Jan 9, 2017 at 12:49
  • \$\begingroup\$ @winny You mean: bonding my body to the ATX case? That way, if the bracket is isolated, then still there can be a potential difference between the motherboard and the new graphics card. \$\endgroup\$
    – user127725
    Commented Jan 9, 2017 at 13:18
  • \$\begingroup\$ Yes. Start by grabbing the graphic card by the bracket and you will be fine. If you have an anti static mat, you can ground that, yourself and both the computer and graphics card by putting tha latter on the mat, professional style. \$\endgroup\$
    – winny
    Commented Jan 9, 2017 at 13:23
  • \$\begingroup\$ Yes, this is what everyone else does. The card doesn't magically acquire a high potential, but humans and their clothing can through tribocharging (rubbing). The "antistatic" bags are usually slightly conductive, enough that simply opening the bag while wearing a wrist strap will equalise it. \$\endgroup\$
    – pjc50
    Commented Jan 9, 2017 at 13:37
  • \$\begingroup\$ Thanks for your answers. Yes, i will discharge myself first. But, if i would be a magician and somehow, without touching anything, i could (by thinking about it) unpack the sealed box (with the graphics card inside) and slide the graphics card into the PCIe x16 slot on the motherboard. (Which is already grounded to earth, thru the case.) Then could the potential difference be big enough to cause a minor ESD-event, in theory? \$\endgroup\$
    – user127725
    Commented Jan 9, 2017 at 14:09

1 Answer 1

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Bad plan because:

no one does it that way because it is not needed

you could cause other problems by making extra connections

The best way to do this is like in your picture but without connecting anything to the graphics card. Personally I would also not connect anything to the PC case because if you place it on the ESD mat, it is sufficiently grounded already.

You're worrying too much about ESD like many people do who do not understand ESD.

A graphics card by itself is not even that sensitive to ESD, you'd have to do crazy things to damage it by ESD. The same is true for the PC's motherboard. With your wristwrap + ESD mat and proper grounding I don't believe you are even capable to destroy anything as no charge buildup can occur.

When you pick up the graphics card and it is charged, it will discharge via you and your ESD wriststrap. You can also place it on the ESD mat and any charge can flow away.

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  • \$\begingroup\$ Thanks for the reply :-) What other problems can happen by making extra connections? \$\endgroup\$
    – user127725
    Commented Jan 6, 2017 at 13:12
  • \$\begingroup\$ Other problems: if you do the connection properly there should be no problem I guess. But the connection is not needed so why make it then ? You misunderstand ESD, if the card is ESD charged, the charge can escape via any connection on the card. ESD is not like a battery which needs a loop. ESD is a charge buildup like in a capacitor. So there is no need for GND and V+ to both touch the mat. The discharge will happen through the metal part near the connectors. \$\endgroup\$ Commented Jan 6, 2017 at 13:21
  • \$\begingroup\$ You might want to read the (long) 2nd post here: eevblog.com/forum/suggestions/episode-suggestion-esd-is-a-myth by AndyC and gain a better understanding. He summarizes the practical implications of ESD. \$\endgroup\$ Commented Jan 6, 2017 at 13:25
  • \$\begingroup\$ Yes! But when V+ and GND are at the same potential (i.e. connecting to the same mat) nothing happens. The charge (inside the GFX card) leaves the card when there's enough potential difference to overcome the resistance (otherwise everything would already been discharged thru the air) or when the resistance suddenly drops, for example: the moment you touch it. This discharging can go 2 ways: from the device to you or the other way around. \$\endgroup\$
    – user127725
    Commented Jan 6, 2017 at 13:27
  • \$\begingroup\$ You're thinking "normal electronics" and not "static electricity". A charge buildup does not behave as you describe. Any conductive path (even many mega-ohms) is enough for the charge to flow away to ground. Any charge difference is enough to cause a discharge once there is a conductive path. Air is an insulator so the charge cannot escape through the air unless the distance is very small (for 1 cm you need about 30 kV potential difference). \$\endgroup\$ Commented Jan 6, 2017 at 13:31

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