the metal fingers that hold the MEMORY
or any of the large metal covers
or the metal attached to the FAN
or any of the Screws on external connectors like the screws holes on each side of the Video connector.
or the metal fingers that hold the Memory modules in place
Or the metal frame of the USB connector on the ThinkPad
See my page on Options for Clips and Probes including making your own probes.
I receive many emails asking about the GND connection, in reality it is very simple, you use some kind of a clip so that you don’t have to hold it in place, you DON’T HAVE 3 HANDS and there are 3 connections, GND SDA and SCL, so have a clip for GND, then you can use the 2 hands YOU DO HAVE to hold your SDA and SCL probes in place.
In the photos below I show an Ezi-hook and an Alligator clip.
If you are using a Large Alligator clip like the one in the photos below, you must make sure the large bare metal of the Alligator clip does not make contact with something other than the metal piece you are connecting to.
Almost any large piece of metal or the screws for the external connectors of any ThinkPad are a good GND connecting point.
Anyway a picture is worth a thousand words, examples of GND connections.
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