Temperature and Noise
Besides the exterior design and modular cables, the cooling system is yet another difference of this model from the Enhance EPS-1280GA.
The previous model used to be cooled by a standard 120mm fan whereas the Enhance EPS-1280GB4 features a 135mm DFB132512 fan from Young Lin Tech.
The EPS-1280GA pleased us with its quietness in our earlier tests but the EPS-1280GB4 is even better! The fan speed remains constant at 800-850 RPM up to a load of 600 watts. After that the fan accelerates in a linear manner, crossing the subjectively comfortable level of 1000 RPM at 750 watts. The speed is only 1150 RPM at full load.
There is no danger of overheat because the difference in temperature between the incoming and outgoing air is 12°C. That’s quite acceptable.
Connected to my APC SmartUPS SC 620, this PSU was stable at loads up to 386 and 280 watts when powered from the mains and batteries, respectively.
Output Voltage Stability
The PSU featuring dedicated voltage regulation (even though not based on the newfangled DC-DC converters), we can expect it to be very good in this test.
The +12V voltage fluctuates within 3% from the default level, preferring high loads: the higher the load on the +12V rail, the closer this voltage is to its nominal value. It is within 2% at loads above 250 watts and within 1% at loads above 400 watts.
The +5V and 3.3V voltages are within 2% of the default levels at typical loads, so this PSU delivers stable voltages indeed.
Output Voltage Ripple
The high-frequency output voltage ripple is within the norm.
The same goes for the low-frequency ripple.
Efficiency and Power Factor
The power factor is just what you can expect from a PSU with active PFC.
The EPS-1280GB4 is over 85% efficient at loads of 20 to 100%. This is a very good result, although its non-modular cousin did somewhat better in this test.
+5V Standby Source
The standby source is okay, but its voltage drop at high load is higher than with the EPS-1280GA.
Just like the earlier-tested Enhance EPS-1280GA, the EPS-1280GB4 is very good electrically. Moreover, it has become quieter and features handy detachable cables. This PSU is going to be a perfect choice for users who want their computer to be quiet even at high loads.