The use of two independent transformers brings advantages and disadvantages. The main advantage is the non-replication of noise and ripple generated at one side to the other side. So if peripherals are generating electrical noise, this noise won't be delivered to the CPU.

On the other hand the maximum power capability from each internal power supply cannot be simply added. You can have a situation where one of the internal power supplies is very loaded while the other power supply isn't delivering a lot of power. This will happen especially if you don't have a multiprocessed system, because nowadays video cards are pulling more power from the power supply than CPUs. 

As for the total power announced by Enermax, one kilowatt, we have great news, even though we didn’t have the necessary equipment to make a true power supply review – we would need to create a real 1,000 W load to check if this power supply could deliver its labeled power or not.

First, the labeled power is rated at 50º C. Why is this important? When the manufacturer doesn’t state the temperature it usually means 25º C. The problem is that when the power supply temperature is increased, its power delivery capability is decreased. This means that a 500 W power supply rated at 25º C won’t be able to deliver 500 W at 50º C – thus this power supply isn’t really a 500 W part, as your power supply will NEVER run at 25º C. Power supplies typically run between 35º C and 40º C. So Enermax is saying that this power supply will deliver 1,000 W even when running hot.

The second thing that is really impressive about this power supply is that all power components can handle much more current/power than stated by Enermax.

Other features from this power supply include high efficiency (meaning a reduction on your electricity bill), active PFC, the use of high-end components, modular cabling system, two fans (with a speed monitoring cable on the smaller fan for you to monitor it using your favorite monitoring program) and several protections. Talking about protections, this unit has a buzzer that will beep if something goes wrong.

With four auxiliary PCI Express power connectors for your quad-SLI system and two EPS12V connectors – supporting up to four CPUs –, you will be able to use this power supply with your very high-end desktop or server.

We were very impressed by the components used inside this power supply, all high-end. From the rectifiers used, we can say that this power supply can probably deliver its rated 1,100 W. Unfortunately we don’t have the necessary equipment to make a true power supply review; we would need to create a real 1,000 W load to check if this power supply could deliver its labeled power or not.

Galaxy 1000 W is a very expensive power supply, though, quoted at USD 360 in the US, three times higher than the average price of good 550 W units. If money isn’t an issue for you this is probably the best high-end power supply money can buy.

However, at least from the theoretical point of view, this power supply should be used only on multiprocessed systems for a better load balancing. If you are running a single CPU with four video cards maybe other 1,000 W products will provide a better power balance (on this example, one of the internal power supplies would be lightly loaded while the other would be heavily loaded).

The only flaw we can say about this product is the absence of a MOV (Metal-Oxide Varistor), which is a transient filter, on its input filter.