# Help with plugs on an old beige Mac G3

**URL:** <https://boards.straightdope.com/t/help-with-plugs-on-an-old-beige-mac-g3/757922>\
**Category:** Factual Questions\
**Created:** [June 20, 2016, 10:10pm UTC](https://boards.straightdope.com/t/help-with-plugs-on-an-old-beige-mac-g3/757922 "2016-06-20T22:10:51Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![randwill](https://avatars.discourse-cdn.com/v4/letter/r/a3d4f5/32.png) [@randwill](https://boards.straightdope.com/u/randwill)\
**Post date:** [June 20, 2016, 10:10pm UTC](https://boards.straightdope.com/t/help-with-plugs-on-an-old-beige-mac-g3/757922/1 "2016-06-20T22:10:51Z")

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I pulled my first computer, a beige Macintosh G3 out of storage today. It booted up great. My problem is, I can’t remember how to hook up the mouse AND the keyboard.

There is one plug-in hole that accepts the plug that is round with one flat side which comes directly out of the Mac keyboard. Looking down into the plug you see 4 tiny pins, two on each side and a rectangular black piece at the bottom (or top, depending on how you hold it). If I plug this into the plug-in hole, the keyboard works.

The problem is, the mouse I have is not the original Macintosh mouse and it has the exact same plug as the keyboard. But there is only one plug-in hole shaped like that on the back of the computer. The mouse works great if I unplug the keyboard from that one plug-in and plug in the mouse there.

I know these parts worked together in the past, but I can’t figure it out. There is just no other place to plug in the mouse (once the keyboard plug-in hole is filled).

Any old Mac experts out there with an idea?

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**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\
**Post date:** [June 20, 2016, 10:17pm UTC](https://boards.straightdope.com/t/help-with-plugs-on-an-old-beige-mac-g3/757922/2 "2016-06-20T22:17:03Z")

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ADB is the plug you describe. Usually there’s an ADB port on the keyboard itself which you can plug the mouse into.

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**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\
**Post date:** [June 20, 2016, 10:17pm UTC](https://boards.straightdope.com/t/help-with-plugs-on-an-old-beige-mac-g3/757922/3 "2016-06-20T22:17:12Z")

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There are two ADB ports on the keyboard - one on each side.

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**Author:** ![randwill](https://avatars.discourse-cdn.com/v4/letter/r/a3d4f5/32.png) [@randwill](https://boards.straightdope.com/u/randwill)\
**Post date:** [June 20, 2016, 10:50pm UTC](https://boards.straightdope.com/t/help-with-plugs-on-an-old-beige-mac-g3/757922/4 "2016-06-20T22:50:55Z")

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Yep. You guys got it. There is a plug cleverly hidden on the underside of the keyboard. Thank you.