The PSU is cooled by a 135x135x25mm fan (Adda ADN512UB-A91). The impeller looks interesting: nine wide blades with small gaps in between.
The PSU is equipped with the following cables and connectors:
- Mainboard cable with a 24-pin connector (49cm long)
- CPU cable with a 4-pin connector (48cm)
- CPU cable with an 8-pin connector (49cm)
- Two graphics card cables with two 6+2-pin connectors on each (50+20cm)
- Two cables with three Molex and one floppy-drive plug on each (50+15+15+15cm)
- Two cables with three SATA power connectors on each (51+15+15cm)
There is nothing to find fault with: the PSU is meant for two graphics cards (which corresponds to its output power) and offers a sufficient number of SATA connectors on two cables. Every cable is sleeved.
The PSU can yield a total of almost 650W across its four “virtual” +12V lines, which is close to its total output power. This is good because the effective output power of the above-discussed A-55GA and P-55GA is far lower than the specified one due to the low load capacity of the +12V rail.
The actual maker of this PSU can be identified by the UL certificate number (in the bottom left of the label). It is Delta Electronics. In fact, Delta offers the GPS-750AB-A model which is identical to the U-75HA in specs and connectors.
The PSU worked continuously under a load of 725W in my tests. It was also stable with my APC SmartUPS SC 620 at loads up to 365W and 335W when powered by the mains and the batteries, respectively.
The output voltage ripple is close to the allowable maximum on the +3.3V rail but low on the other two rails.
The +12V voltage is very stable, only deflecting by 1% in a very small part of the diagram. The +5V is somewhat worse, keeping within a 3% deflection. The +3.3V voltage sagged below the permissible limit but only under extremely high loads. This is a visible difference from the previous two models!
The PSU reaches 80% efficiency at 100W (13% from the maximum) and then goes as high as 87%. The power factor is very close to 1.
The fan speed is no higher than 900rpm at loads below 500W, making the PSU quiet, almost silent. Then the speed grows up. The rumble of the impeller and the hiss of the airflow are audible at a load of 600W (fan speed of 1200rpm). The PSU is quiet overall.
Thus, the ASUS Vento U-75HA boasts good characteristics including high output power (I mean the effective, not just specified, output power), good stability of the output voltages, high efficiency, and quiet operation. This PSU can be recommended for top-end gaming stations as it can easily handle a couple of graphics cards (or one dual-GPU card like Radeon HD 4870 X2).