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Cougar SX550 Review

Manufacturer: Cougar
UK price (as reviewed): £79.99 (inc VAT)
US price (as reviewed): Not Available

Cougar is a relatively new name in the PSU market and is a subsidiary of the Taiwan-based HEC group, which traditionally specialises in supplying cases and power supplies to system integrators (it also makes the SX550, rather than using another maker). The Cougar brand is targeted directly at computer enthusiasts and gamers, however, with all the PSUs being designed at its headquarters in Germany.

Externally, the SX550 is a feast for the eyes, as its case has an attractive mottled finish and burnt orange detailing that looks great. The cable braiding follows the same black, orange and silver colour scheme too, which gives the long cables a distinctly snake-like appearance. The majority of these cables are modular, meaning that the bottom of your case has no reason to resemble a snakepit. Only the 24-pin ATX, 8-pin EPS12V, 6+2-pin PCI-E and a single 6-pin PCI-E connector are hard-wired into the PSU.



As a result, there’s no need to connect the five Molex sockets, seven SATA connections and the additional three 6-pin PCI-E connections if you don’t need them. It’s worth noting that the SX550 is also the only sub-600W PSU on test with four PCI-E connectors, even if three of them are only 6-pin plugs.

The SX550 spreads its connections over four 12V rails, with the first taking care of the 24-pin ATX connection, and the SATA and Molex sockets, while the second is dedicated to half of the 8-pin EPS12V plug. Meanwhile, the third and fourth rails supply a pair of PCI-E connections each, with the third rail also taking responsibility for the second half of the 8-pin EPS12V connection.

The SX550 sat towards the top of the table when it came to efficiency, as it was 89 per cent efficient at 50 per cent load and 86 per cent efficient at 100 per cent load.

It was also 100 per cent stable throughout our testing; none of the rails strayed above or below the ATX spec, even at 100 per cent load. The 12V rails proved particularly stable as well, varying by only 0.27V between our 10 per cent and 100 per cent load tests.

The fan cooling the SX550 proved to be on the loud side, however, emitting a constant audible hum, regardless of how much load was passed through the PSU. The SX550’s holdup performance was also a little less than brilliant – the 5V rail held its charge for an impressive 31ms but the 12V rail we tested dropped after just 16ms, which is below the level recommended by the ATX specification.

Meanwhile, the second of our new tests – the ripple test – proved to be an area of strength for the SX550, as its peak ripple amplitude of 11.4mV was among the lowest results we saw.

The SX550 is a good effort from Cougar, as it’s stable and looks good. Unfortunately, though, the Seasonic X-560 is quieter, totally modular, has better holdup times and is more efficient.