Power Supplies with 12V Rails Listed Separately

Some power supplies list multiple 12V Rails. Most of the time these power supplies are concerned with meeting 240VA Safety requirements, and to meet these Safety requirements, the PSU provides multiple 12V rails. Figure 3-2 is provided as an example of this type of power supply.

Figure 3-2: PSU Label with Multiple 12V Rails

Power supplies with multiple 12 Volt rails follow these breakdowns for each 12V rail:

• 12V1 = Main Board and storage power connectors,
• 12V2 = processor power connectors,
• 12V3 and 12V4 = discrete graphics card power.

In this scenario, determining CPU support it is very simple: look at the current rating for the 12V2 rail and determine if it is able to provide enough continuous current for the processor to be used.