This 650 W power supply from looks like a very high-end unit, as it is bigger than traditional power supplies and uses a dual-transformer design, feature we’ve only seen on power supplies on the 1,000 W range like Enermax Galaxy 1000 W and Tagan TurboJet TG1100-U95 1,100 W. It is also cheaper than competing products from better known brands. Is it a good product? That is what we are going to find out. WattSmart 650 WFigure 1: WattSmart 650 W power supply. WattSmart 650 WFigure 2: WattSmart 650 W power supply.

As mentioned, this power supply is bigger than regular power supplies, being 7 31/64” (19 cm) deep, while regular power supplies are 5 33/64” (140 mm) deep. So the first thing you need to check before buying this unit is if it fits your case. This shouldn’t be a problem if you are using a good case.

This power supply uses two 80 mm fan, one on the front side and the other on the rear side. We prefer power supplies with big 120 mm or 140 mm on the bottom, as this configuration provides a better airflow and lower noise level, but maybe this kind of fan wouldn’t fit this power supply because of the size of the heatsinks inside the unit.

Like all high-end units today, this power supply features active PFC and high efficiency (at least 80%, according to the manufacturer). Active PFC provides a better utilization of the power grid and allowing the manufacturer to sell this product in Europe (you can read more about PFC on our Power Supply Tutorial).

The higher the efficiency the better – an 80% efficiency means that 80% of the power pulled from the power grid will be converted in power on the power supply outputs and only 20% will be wasted. This translates into less consumption from the power grid (as less power needs to be pulled in order to generate the same amount of power on its outputs), meaning lower electricity bills – compare to less than 70% on regular power supplies.

This power supply comes with six peripheral power cables: two auxiliary power cables for video cards with 6-pin connectors, two cables containing three standard peripheral power connectors and one floppy disk drive power connector each and two cables containing three SATA power connectors each.

The number of connectors is good enough even for high-end users with a big RAID array and two video cards in SLI or CrossFire configuration.

The main motherboard cable uses a 20/24-pin connector and this power supply comes with both ATX12V and EPS12V connectors.

On the aesthetic side the manufacturer made a great job. All wires have a nylon sleeving coming from inside the power supply housing and going all the way to the end of the cable using a top notch rubber to make the finishing, as you can see in Figure 3. WattSmart 650 WFigure 3: Nylon sleevings go all the way to the end of the cables.

All wires used on this power supply are 18 AWG, which is correct for a power supply from this power range.

This power supply is manufactured by ATNG, which also manufactures power supplies sold in the USA as Rosewill.

Now let’s take a look inside this power supply.


Gabriel Torres is a Brazilian best-selling ICT expert, with 24 books published. He started his online career in 1996, when he launched Clube do Hardware, which is one of the oldest and largest websites about technology in Brazil. He created Hardware Secrets in 1999 to expand his knowledge outside his home country.