Features, specifications, and a closer look

Below are the features and specifications taken from the “Potency 550W” product page:

• 80 PLUS Certified
• SLI Certified
• Active PFC
• Support 9800 GX2
• Full Circuit Protection (OCP/UVP/OVP/SCP/OLP)
• Silent 120mm Sleeve Bearing Fan
• 3-year Warranty
• Size: 140 mm x 150 mm x 86 mm

Output specifications:

Connectors:

• 1 x 20+4-Pin Mainboard
• 2 x PCI Express (1 * 6Pin, 1 * 6+2Pin)
• 1 x 4-Pin Molex Y Cable
• 4 x 4-Pin Molex
• 1 x 4-Pin FDD
• 4 x SATA
• 1 x 8-Pin EPS12V
• 1 x 4-Pin P412V

The Tuniq Potency 550W offered a fairly typical set of specifications, but there were a few noteworthy features. Firstly, Tuniq decided to opt for two 12V rails that each deliver 25A of current. This is a little high for a dual rail PSU, as the official ATX specification calls for a maximum of 18A per rail. This begs the question: why use two rails at all?

You’ll notice that the maximum combined power for the 12V rails is 450 watts. The magical “ohms law” calculation tells us that although each 12V rail could theoretically output 25A, both cannot produce 25A simultaneously.

We suppose that two 25A rails sounded better than a single 37.5A rail, which is really the maximum specified 12V current that this PSU could provide. We do believe, however, that the output characteristics of the PSU are adequate for a 550W rating and the sorts of systems it will likely be used with.

Tuniq appears very confident in the abilities of their Potency 550W by seeking and receiving NVIDIA’s “SLI Certified” stamp of approval; Tuniq goes so far as to say that this unit supports a 9800GX2 graphics card. You won’t find statements like that printed on those beer-can PSUs that come with cheap cases at your local computer shop!

When it comes to connectors, the Potency delivered a fairly standard spread. We were pleased to see that one of the unit’s two PCI Express connectors was an 8-pin model, which made the Potency a suitable choice for power-hungry cards like the 9800GX2 or a pair of 4850s.

The Potency 550W came in a simple black enclosure with a finish of moderate durability. The enclosure itself is sized to the PS2 ATX specification, which means it would fit in virtually any standard case.

The rear of the PSU employed a honeycomb-style grille for minimal restriction of airflow. While an on/off toggle was located at the rear of the PSU, there was no 110/220V switch. Since the Potency is an active PFC unit, it can accept a wide variety of input voltages from 100-240V AC. Our friends across the pond can simply plug it in and be off to the races.

The Potency 550W is not a modular PSU, so you’ll have to live with the bird’s nest of cables protruding from it. Thankfully, Tuniq has fully-sleeved them to prevent tangles and improve aesthetics.

Tuniq included some case screws, a 4-pin Molex splitter and even a bunch of zip-ties with the Potency 550W.

The internal components of the Potency 550W were sized appropriately for its rated output. The capacitors were 105°C-rated models made by “PEC.” The components within were spaced well, but we were pretty disappointed with the heatsinks within. They were essentially two thin aluminum plates without fins. Heat dissipation could have been improved greatly with a better internal heatsink design.

The two 12V rails appeared to be split appropriately, with +12V1 used for the mainboard connectors and the +12V2 rail for the PCI-Express leads. The fan used in the Potency 550W was a sleeve-bearing model rated for a relatively low 0.18A of current draw at 12V.