How to clean edge connectors on cards

Technicians agree that the most difficult troubleshooting involves intermittent symptoms, and that many of these can be traced to dirty electrical connections or connectors.

Inspecting an Edge Connector

Make sure the card is not receiving electrical power. If necessary, turn off and unplug the device housing the card.
Touch an electrically grounded area to rid yourself of static electricity. For example, touch the power supply or the metal chassis frame of the computer. Once this is done, do not shuffle your feet or move your body in a way that will create a new static electric charge.
Handling the card by its edges as much as possible, remove the card from its slot or connector. Do not touch electronic components or the edge connectors.
Visually inspect the edge connectors for signs of dirt or contamination. A magnifying glass may help.
Cleaning an Edge Connector
Here are two methods for cleaning edge connectors:
Pencil eraser
Use an ordinary pencil eraser to clean the edge connectors. Blow the eraser crumbs away; do not wipe them away with your fingers.
Stabilant-22A
Stabilant 22-A is a contact-enhancing product by D.W. Electrochemicals Ltd.; their website is at http://www.stabilant.com/ .
Stabilant 22-A is a non-conductive block polymer that becomes conductive in the presence of an electrical field or when placed in a very narrow gap between electrical contacts. It remains non-conductive between adjacent contacts in a multiple-pin environment. Users of this product report that it works well on a variety of connections. It can also be used for audio and video connectors.
[Important: Information about products not manufactured by Apple is provided for information purposes only, and does not constitute Apple's recommendation or endorsement. Please contact the vendor for additional information.