It's pretty simple.
The conductive pen traces a line from point a to point b.
When they are joined, they let electricity pass thru, thus giving the card more voltage.
a resistor is exactly what it sounds like. It's an electronic component that resists the flow of electrical current. The Resistance is measured in OHM (Ω).
For memory volt mods, you can take a number #2 penicl, and shade a resistor with you eraser thus decreasing the OHM and letting more electrical current pass by, allowing better overclocking.
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