In Figure 15, you can see the power supply label containing all the power specs.

click to enlarge
Figure 15: Power supply label.

This power supply has two virtual rails, distributed like this:

• +12V1 (solid yellow wire): All cables but the ATX12V/EPS12V cable.
• +12V2 (yellow with black stripe wire): ATX12V/EPS12V connectors.

This is a somewhat adequate distribution for a power supply with two rails.

Now let’s see if this power supply can really deliver 550 W.