OCZ GameXstream 700 W Power Supply

Power Distribution

In Figure 15, you can see GameXstream 700 W label stating all its power specs.

Figure 15: Power supply label.

This unit has four +12 V virtual rails, distributed like this:

• +12V1 (yellow with blue stripe wire): One of the ATX12V connectors ("CPU 1").
• +12V2 (yellow with green stripe wire): The other ATX12V connector ("CPU 2") and one of the video card auxiliary power connectors ("PCIE-2").
• +12V3 (solid yellow wire): Motherboard main cable, peripheral power cables and SATA power cables.
• +12V4 (yellow with black stripe wire): The other video card auxiliary power connector ("PCIE-1").

Figure 16: +12 V wires are separated into four virtual rails.

From the previous page we came with some maximum theoretical numbers for the +12V output (1,029 W), +5 V (214 W) and +3.3 V (141 W).

As we mentioned earlier the maximum current/power each line can really deliver will depend on other components, especially the transformer, the coil, the wire gauge and even the width of the printed circuit board traces used.

We found some funny things on this power supply label.

For the +12 V output OCZ stated 18 A for each one of the power supply four virtual rails. This would give a 216 W per rail or 864 W total – OCZ labeled +12 V total power as 680 W. Oh, there is a small phrase there “Maximum combined current for the +12 V outputs shall be 50 A.” Well, if we do the math, the maximum power for the +12 V outputs combined would be 600 W – and not 680 W as printed on the label. Why printing conflicting numbers?

For the + 5 V output OCZ stated a 30 A maximum current, which translates to 150 W, while for the +3.3 V output the manufacturer stated a 36 A maximum current, or 118.80  W. On the label, however, OCZ says that the combined power of +3.3 V and +5 V outputs is of 155 W (since they are connected to the same transformer output). Here it is funny to notice that Corsair HX620W, a 620 W power supply, has a combined power of 170 W, more than this 700 W power supply.

Anyway, all positive outputs are labeled with a current well below the maximum current each rectifier can deliver.

Unfortunately we don’t have the necessary equipment to make a true power supply review; we would need to create a real 700 W load to check if this power supply could deliver its labeled power or not.

Also, as a final note, OCZ doesn’t specify the temperature under which the power supply is rated. Usually when no temperature is stated, the manufacturers assume 25° C, which is a temperature far below the power supply real working temperature. Keep in mind that the maximum power a power supply can deliver drops as its internal temperature increases.