Definition
An edge connector is the row of flat metal contacts along the edge of a printed circuit board that plugs directly into a matching slot, with no separate plug attached. The board's own edge is the connector. It is one of the cheapest and most reliable ways to join a card to a host, which is why it shows up on everything from graphics cards to mining hashboards.
How it works
The contacts, usually called fingers, are exposed copper pads plated with gold to resist corrosion and wear from repeated insertion. They line up with spring contacts inside a socket, and the slot's housing holds the board mechanically while the fingers carry power and signals. Designers often stagger the finger lengths so that ground and power make contact a fraction before the signal lines, which protects the electronics during insertion. A keying notch in the row stops a card from being seated backwards or in the wrong type of slot.
Where you meet it in mining hardware
The most familiar example is a PCI Express graphics card, whose gold fingers slot into the motherboard or into a powered riser in a GPU mining rig. Inside ASIC miners, hashboards frequently connect to the control board and power domain through edge connectors or closely related card sockets, which keeps the assembly serviceable: a failed board can be unplugged and swapped rather than de-soldered. Because the contacts are exposed, they are also a common fault point. Oxidised or dirty fingers cause intermittent connections, and a careful clean of the edge is a standard early step when a board behaves erratically.
For the high-speed bus that the best-known edge connector carries, see PCI Express.
In Simple Terms
An edge connector is the row of flat metal contacts along the edge of a printed circuit board that plugs directly into a matching slot,…