Cooler Master's Real Power Pro 550W
For reals, yo

Cooler Master makes loads of power supplies, and we have two units in our group. The first is the Real Power Pro 550W, which currently sells for a little less than $100. This price tag makes the Pro one of the most affordable PSUs of the bunch, but don't assume Cooler Master has skimped on features. The Pro boasts 80 Plus and SLI certifications and packs a trio of independent 12V rails.

Warranty coverage is limited to three years, though. That's not quite as nice as the five-year guarantees offered by some other manufacturers, but it should be enough for most folks.

Those with an eye for aesthetics will no doubt appreciate the Pro's glossy black finish. If you enjoy silence, the unit's temperature-controlled 120mm fan should catch your eye, as well. Like most PSUs with bottom-mounted cooling fans, the Pro features extensive venting at the rear.

Note the little LED next to the Pro's power switch. This LED serves as a warning system and will light up if the power supply detects that voltages, temperatures, current, or even the load deviates from acceptable levels.

The Real Power Pro doesn't come with modular cables. Cooler Master has done a good job of ensuring that all leads are neatly sheathed, though. Sheathing doesn't affect power delivery, but it makes snaking wires around an enclosure a little easier, and the end result looks a lot nicer.

DC voltages look solid for the Real Power Pro across all three loads. Any deviations from target voltages are at or below 1%, which is quite good.

Ripple is consistent for the Real Power Pro, as well. AC content does trend a little higher than we saw with the Antec models. However, we're still looking at averages below 18 millivolts overall—well within an acceptable range.

Despite its 80 Plus certification, the Pro only manages 79.4% efficiency under our 100% load. The Pro does better under loads of 50 and 75% of capacity, where it maintains greater than 80% efficiency.

Update 10/05/2007 — Cooler Master has bumped the warranty coverage of its Real Power Pro power supplies to five years.