Zalman ZM850-HP Plus Power Supply Review

Power Distribution

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

Figure 15: Power supply label

This power supply has four  +12 V virtual rails, and we could confirm this by the presence of individual over current protection circuits attached to each rail (see Figure 16). Click here to learn more about this subject.

Figure 16: “Shunts” (current sensors)

These rails are distributed like this:

• +12V1 (yellow/black wire): One of the ATX12V connectors (half of the EPS12V connector), one of the video card cables from the modular cabling system, peripheral power connectors
• +12V2 (solid yellow wire): Main motherboard cable, one of the ATX12V connectors (half of the EPS12V connector)
• +12V3 (yellow/blue wire): The video card cable that is permanently attached to the power supply
• +12V4 (yello
  w/green wire): One of the video card cables from the modular cabling system, SATA power connectors

With four rails and three video card cables, the manufacturer should have put each video card cable on a separate rail and the CPU on the fourth rail. However, they split the CPU power connector in two separate rails, making half of the EPS12V connector to be mixed with one of the video card cables. So, for a better power distribution, we recommend you to use the video card cable that is permanently attached to the power supply and the connector of the modular cabling system that is closer to the cables that are permanently attached to the power supply, as this is the connector attached to the +12V4 rail, avoiding the connector that is available in the middle of the modular cabling system, which is the one that shares the rail with the EPS12V connector.

Let’s now see if this power supply can really deliver 850 W.