Coolermaster Centurion 5 mid-tower case

The Centurion 5 came bundled with a Coolermaster Real Power RS-350-AMSR 350 watt PSU. Again, here are Coolermaster's own words on the product:

PSU information from Coolermaster
Power Supply is a key component to supply all power requirements in supporting PC operation to maintain continuous stability and reliability of a computer system. Cooler Master power supply lets your PC operate better and more efficient, with the best power source as it comes into your PC. It also enhances system reliability by preventing mains abnormal supply from spikes and surges. In addition, the power supply provides your system with perfect protection. RS-AMSX is a standard ATX-12V PS2 power supply offering more power capacity for CPU usage.
Features
Super Silent 350W with intelligent fan control (<23dB) Fully supports Intel ATX 12V V1.2 for Intel® and AMD systems High efficiency and reliability (MTBF > 100,000 Hrs @ full-load / 25 Degree C) Green power design to meet blue angel and energy star (<1W @ Standby Mode) SATA and external fan connectors for next hard drive and system fans Real power capacity satisfy hungry hi-end system operation Over voltage, current, temperature, and short circuit full protection
Specifications
Voltage		90V~132V or 180V~264V (Selectable)
Current		10A @ 115Vac / 5A @ 230Vac
Frequency		47Hz~63Hz
Hold-Up Time		> 16ms @ Nominal Input Voltage
Efficiency		> 70% @ Full Load
Dimensions		PS/2-ATX form factor: approx 15cm x 8.6cm x 14cm
Operation Ambient		0 to 50 degrees C, to 90% relative humidity, 10,000 ft
Storage Ambient		-20 to 60 degrees C, to 95% relative humidity, 50,000 ft
MTBF		> 100,000 Hours
EMC		FCC / CE / CNS
Safety		UL / cUL / TUV / NEMKO

Output Specifications
Output Voltage Line	+3.3V	+5V	+12V	-12V	+5Vsb
Max. Current	18	25	16	1.0	2.0
Max. Power	160W		168W	12W	10W
Max Combined Power	328W			22W
Static Regulation	+/-5%	+/-5%	+/-5%	+/-10%	+/-5%
Ripple/Noise	50mV	50mV	120mV	120mV	50mV
Cabling
* 2 dedicated fan only connectors, which supply 12V only * Pair of SATA connectors * 2 strings of 2 4-pin Molex,, 1 floppy * 1 AUX 12V connector * ATX connector

PSU TESTING

A recent addition to the testing tools at my disposal is a PSU loading and testing device from Seasonic, the power supply company. In essence it is a rudimentary version of the elaborate PSU-tester that Mike employs for in-depth PSU reviews. It consists of two components: A two-step PSU loader, and a Power Angel multifunction meter.

The PSU loader has two preset load levels:

• 75.1 Watts (comprised of 12.0 amps on the +3.3V, 3.5 amps on the +5V, and 1.5 amps on the +12V rails)
• 137.6 Watts (12.0A, 10.0A, and 4.0A, respectively)

These are pretty good average loads for a typical PC at idle or low load, and at maximum load.

The Power Angel is a new-and-slightly-improved model of the Kill-a-Watt AC power meter that has been in use on SPCR for quite some time.

Seasonic PSU load tester on top left: It is housed in an ATX PSU enclosure and has a cooling fan, but it is not a PSU. The Seasonic Power Angel AC power meter is directly beneath it, showing 88W AC power input to the PSU under 75W DC output load on the right. (Note: This is not the PSU tested in this review.)

By loading the PSU at the two preset wattage levels, and then recording the AC power from the Power Angel, a snapshot of the PSU's efficiency can be calculated.

The testing confirms Coolermaster's claim of >70% efficiency at load. That's a pleasant surprise from what is an otherwise unremarkable unit. The power factor readings are a clear indication that the RS-350-AMSR has neither active nor passive PFC.

One claim on the spec sheet that cannot be validated is the noise level of <23dB. Even at startup, the single 80mm fan is beyond that number, and the noise only climbs as the load increases. The no-name ball bearing fan is clattery, and exhibits a high degree of turbulent wind noise. The relatively high efficiency may make the RS-350-AMSR a good candidate for a fan swap, however, which would go a long way towards improving the sonic character of the unit.