Akasa Power+ 650W Power Supply Review

Introduction and Features

The Akasa Power+ is a heavy duty power supply is rated for 650W. It features four +12V outputs, comes with two PCI-e connectors and uses dual 80mm cooling fans. The Akasa 650W PSU delivers solid, stable outputs but is far from quiet.

The Performance Series Power+ 650W power supply from Akasa is reported to be very popular in Europe and features heavy duty construction, four independent +12V outputs, and support for multi-CPU motherboards.  The Akasa 650W power supply unit (PSU) was designed for hi-performance desktop systems and incorporates dual fans in a push-pull configuration for exceptional cooling.  The Akasa PSU comes with sleeved cables, a wealth of connectors, and active PFC with universal AC input.

Akasa AK-P650FH PSU Key Features (from the Akasa website)

In addition to the power supply the Akasa box also includes a power cord, mounting screws, and a 4-pin to dual 3-pin fan adapter cable.

The Akasa Power+ 650W power supply was evaluated on both features and performance.  A full range of equipment was used to test the power supply under controlled load conditions.  In addition to measuring the power going in and coming out I looked at voltage regulation, electrical noise (AC ripple), sound level, efficiency and cost.  Here is a list of the equipment used during testing.

• FLUKE 87-III True RMS digital multimeter (Accuracy +/- 0.05%)
• WattsUp? Pro — digital wattmeter (Accuracy 3% of full scale)
• Hitachi V-650F 60 MHz dual trace oscilloscope (Accuracy +/- 3%)
• Powerstat Variable Autotransformer, 1.4 KVA, 0-140 VAC
• FLUKE  52-II digital thermometer (Accuracy +/- 0.3ºC/0.5ºF)
• Extech Model 407736 digital sound level meter (Accuracy +/- 1.5 dB)
• AccuLab V1-10kg digital balance (Accuracy +/- 1g)
• Homemade PSU load tester — selectable loads (up to 470W)
• Seasonic PSU load tester (up to 137W)

Establishing a controlled load is critical to testing and evaluating a PC power supply.  I built my own power supply load tester using 13 wire-wound, ceramic resistors of various sizes.  This unit can now place up to a 470 watt combined load onto the power supply being tested and includes independent +12V1 and +12V2 loads.  Different combinations of resistors can be switched in or out to select various loads.  In addition to my own load tester, I also used a load tester manufactured by Seasonic (75W and 137W loads).