The specifications do not coincide with any model from CWT and mostly lie in between those of the CWT PUQ (B) models with wattage ratings of 750 and 850 watts.
The Corsair GS800 permits a higher combined load on the +5V and +3.3V rails than the Channel Well products from the mentioned series: 150 instead of 130 watts. But the load on each individual rail is limited to 25 amperes with any PSU based on this platform, including the GS800.
The GS800 complies with the 80 PLUS Bronze standard.
Working together with our SmartUPS SC 620, this PSU was stable at loads up to 375 watts when powered by the mains but couldn’t switch to the UPS’s batteries even at 280 watts.
Cross-Load Voltage Stability
Every voltage always remains within 3% of the required level in this PSU:
Compared to the Chieftec BPS-850C2, which is based on the same platform, the Corsair GS800 performs more consistently in this test. Its voltages deflect by the same amount on each power rail whereas the +12 and +5 voltages of the BPS-850C2 were more stable than its +3.3V voltage.
Output Voltage Ripple
The Corsair GS800 is preferable to the Chieftec BPS-850C2 in terms of voltage spikes:
The high-frequency ripple isn’t as good as with the best PSUs we’ve seen, yet easily meets the industry requirements.
The low-frequency ripple is even weaker, the perfect picture being only spoiled somewhat by the occasional spikes on the +12V rail.
Temperature and Noise
The Corsair GS800 is cooled by a 7-blade 140mm Ong Hua HA1425H12B-Z fan. It is partially covered with a piece of plastic to optimize air flows inside the PSU case.
The fan doesn’t work at all at low loads, making the PSU absolutely silent. It is only at loads over 200 watts that the fan turns on for a while at a low speed. It begins to work without intermissions at loads higher than 300 watts. Unfortunately, the fan isn’t quiet even at the minimum speed, producing some rattle.
As soon as the fan gets to work constantly, its speed accelerates in a linear manner. The subjectively comfortable limit of 1000 RPM is reached at a load of 450 watts. At full load the fan works at 2100 RPM.
Thus, it is hard to evaluate the Corsair GS800 in terms of noisiness. On one hand, it is silent at very low loads but, on the other hand, it is too loud for its class at high loads.
Efficiency and Power Factor
The Corsair GS800 was 87.8%, 89.3% and 85.3% efficient at the reference loads of 20%, 50% and 100%. Like the similarly-designed Chieftec, it meets not only 80 PLUS Bronze but even the 80 PLUS Silver requirements. The peak efficiency was 89.9% at 292 watts.
The power factor is close to 99% at high loads, which is what you can expect from a PSU with active power factor correction.
The standby source works flawlessly.
The Corsair GS800 is very similar to the Chieftec BPS-850C2 except for minor differences. It is somewhat better in terms of output voltage ripple and features an original exterior with a highlighted fan. The Chieftec, on its part, offers more output power, has modular cables and is somewhat more efficient.