Enermax Liberty 620W Modular Power Supply

Load Test Results:

Loads are reported at 4 different levels (Low, Typical, Heavy, and Max), the numbers will vary slightly between power supplies because voltage levels have a direct effect on current going though the resistors. Ambient temperature (outside the case) would vary between 23.8-26.7°C (75-80°F), which was somewhat proportional to the load level being tested, however the main concern was keeping the internal temp below 50°C. All PC power supplies are "switching power supplies", so please keep in mind that voltage levels will always vary between PCs because loads are always different (and quite dynamic).

• Things to consider:
  1. Voltage Regulation (% above/below nominal)
  2. Efficiency (particularly under a "typical" & "heavy" loads)
  3. Safety (Does it shutdown under unsafe conditions?)
  4. Maximum Real Power Output (does it meet rated output?)
  • Potential reasons a power supply did not meet its rated maximum power output:
    1. Voltage exceeded maximum tolerances
    2. PSU shutdown (overheat or overload condition)
    3. Load tester would of exceeded PSU specs for combine rail wattage
    4. PSU rating exceeds max load capable by tester (only relevant on 12V)

We try to get as close as possible to the maximum PSU rated output, but the design of the load testing device only works in incremental numbers. This results in a final load that might be slightly above or below the PSU's rated spec.

The table below shows the tolerance voltages for reference with the above numbers. ATX12V guidelines allow for a ±5% tolerance on all rails, except for the -12V which has ±10%. Under peak loading the 12V outputs can go to ±10%.

To see how this power supply compares against other PSUs, please visit our compiled results page.

Comments:

• 120mm fan stayed reasonably quiet, even under heavy loads.
• Very good efficiency, >80% under typical loads.
• PSU maxed our 12V load tester circuits at ~18A each.
• Over-Current, Over-Load, Short-Circuit, and Over-Temp protection were all tested and functioned as expected.