Hardware Reference
In-Depth Information
the latch on the side might not engage, but the connector will otherwise plug in and operate properly.
Figure 18.29
shows how you would connect a new power supply with a 24-pin connector to a
motherboard that has only a 20-pin socket. The terminals on the 24-pin connector that are highlighted
in gray would plug directly into the 20-pin socket, whereas the white highlighted terminals would
remain free and unconnected.
Figure 18.29. Connecting a 24-pin main power connector to a 20-pin motherboard socket.
Logically, this works because the first 20 pins of the 24-pin connector that match the 20-pin
motherboard socket contain the correct signals in the correct positions. The only problem that might
arise is if there are some components on the motherboard directly adjacent to the end of the 20-pin
power socket that physically interfere with the four extra unused terminals on the 24-pin connector.
What about the opposite condition, in which you have a new motherboard with a 24-pin socket but
your power supply has only a 20-pin connector? In this case, four terminals at the end of the
motherboard socket are not connected. This also works because the 20-pin portion of both the
connector and socket are the same. But this example raises another question: Will the motherboard
operate properly without the extra power pins? Because the extra signals are merely additional
voltage pins that are already present in the remaining part of the connector, the answer should be yes,
but if the motherboard draws a lot of power, it can overload the remaining pins. After all, preventing
