Seasonic S12 500W 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?)
  • Two potential reason a power supply did not meet its rated maximum power output:
    1. Voltage exceeded maximum tolerances
    2. PSU shutdown (overheat or overload condition)

Note: Maximum tested load (red background) may not always be the maximum PSU output rating (mentioned as reason #4 above). We try to get as close as possible to the maximum rated output, but the design of the load testing device only works in incremental numbers so it may be slightly higher or lower.

AC Ripple Test Results:

Using a Tektronix 2215 Oscilloscope, we check for AC ripple that is present in the DC power. We only checked the +3.3V,5V,+12V1, and +12V2 rails (not the -12V or 5Vsb). Potential frequencies could be in the 60Hz range (which is what the AC line power is in the US), or in the higher KHz range closer to the PSU's switching frequency. The guideline tolerance is 50mV p-p on the +3.3V & 5V rails, and 120mV p-p on the +12V1 & +12V2 rails.

To see how these power supplies compare against other PSUs, please visit our compiled results page that includes all previous PSU testing results.

Comments:

• 12V rails loaded to ~17.5A each (max we can test), voltages stayed within acceptable levels.
• Excellent efficiency, 85% under typical load! Also has active PFC!
• 12cm fan was very quiet under typical conditions, under max load it would spin up.
• Could not get PSU to shutdown from current or temp overload. Voltage levels would just continue to drop and current would never go higher than about 720W (AC, so figure about 560W DC).