The forthcoming Corsair HX1000W is labeled with the rates shown on Figure 5.

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Figure 5: Corsair HX1000W power ratings.

Since this power supply has two real rails, each one coming from independent transformers and rectifiers, each +12 V rail has a higher current limit compared to traditional power supplies. Also, as you can see, this power supply does not use the virtual rail concept: each +12 V line comes from an independent source, and not from a single source like regular units.

On this power supply the +5 V output is produced by one transformer and the +3.3 V output is produced by the second transformer. This is great because usually even on power supplies that have two separated rectifiers for the +3.3 V and +5 V outputs they are produced from the same transformer output, so the maximum current these two outputs can pull is limited by the transformer. That is why you usually see that +5Vand +3.3 V outputs have a higher current/power limit when listed alone, but together they have a lower current/power combined limit. This doesn’t happen with this unit.

The thing that most caught our attention was the 40 A limit for each +12 V rail. This translates into 480 W on each +12 V rail. The +5 V rail is rated at 30 A or 150 W (30 A x 5 V) and the +3.3 V rail is also rated at 30 A or 99 W (30 A x 3.3 V). This power supply could be easily labeled as a 1,200 W unit by an unscrupulous manufacturer, but Corsair decided to play it safe and limited each transformer at 500 W.