We have never tested Huntkey products in our labs and there is one critical remark right from the start: calling an 800-watt model “HK901-11PEP” does not sound good to me.
We’ve got a standard black power supply here. The chrome-plated fan grid is the only remarkable feature. The PSU is rather compact, measuring exactly to accommodate the 14cm fan.
Like most other PSUs in this review, the HK901 is modular. There are eight connectors for cables on its back panel. The connectors differ in color and keys, but you should not blindly rely on the latter as they allow pushing an HDD power cable into a 6-pin connector for a graphics card cable.
There are two things I can note about this design: the component density is very high and there are very small heatsinks on the power semiconductor components. The heatsinks are nothing more than thick but absolutely finless bars of aluminum. The PSU needs to be highly efficient or have a fast fan in order to cool such heatsinks, considering the high component density. You’ll learn shortly which way the developer went with this product.
Otherwise, the PSU is quite a standard device and does not even try to match the products from Enermax and Seasonic in terms of innovations per cubic centimeter. Like all other models in this review, it features dedicated voltage regulation but it is based on chokes (a magnetic amplifier design) rather than on DC-DC converters.
Looking at the label, you can once again note the discrepancy between the numbers in the PSU name (HK901) and specified output power (800 watts). You can also take note of the high load capacity and “classic” splitting of the +12V power rail into 18-ampere lines. In most power supplies of similar wattage that retain this split-rail design, the graphics card power lines have a max current of 22-25 amperes, which ensures more flexibility in connecting the load. To remind you, overloading one “virtual” power line triggers the PSU’s protection and shuts the whole PSU down although the latter might still be a large reserve of output power.
Cables and Connectors
This PSU is equipped with the following cables and connectors:
- Mainboard cable with a 24-pin connector (46 cm)
- One connector for a CPU power cable
- Three connectors for peripheral power cables
- Four connectors for graphics card cables
Included with the PSU are:
- One CPU cable with a 4+4-pin connector (50 cm)
- Two blue graphics card cables with two 6-pin connectors on each (50+15 cm)
- Two blue graphics card cables with one 6+2-pin connector on each (50 cm)
- Two red graphics card cables with one 6-pin connector on each (50 cm)
- One cable with four PATA power connectors (50+15+15+15 cm)
- One cable with three SATA power connectors and one PATA power connector (50+15+15+15 cm)
- One cable with three SATA power connectors and one floppy-drive plug (50+15+15+15 cm)
The color of the graphics card cables must be matched with the color of PSU connectors: the red ones are for 6-pin connectors and the blue ones are for 8-pin connectors. The four PSU connectors and six cables offer you more flexibility: you can power two top-end graphics cards or three mainstream graphics cards, for example.
I like the cable with three SATA and one PATA power connector. The latter is usually used in a modern computer for powering a fan or some indicator panel, etc. There is no point in using a separate PSU cable for that.
Working with my APC SmartUPS SC 620, this power supply was stable at loads up to 355 watts when powered by the mains and up to 350 watts when powered by the batteries. They switched to the batteries normally and the UPS worked for half a minute but then reported overload and shut down. Thus, you need an UPS with a reserve of wattage (compared to the real power consumption of your computer rather than to the specified output power of the PSU) or with a sinusoid output voltage for the HK901-11PEP.
Output Voltage Stability
We can only see some red color in the diagram when the +5V voltage gets to its permissible limit under extremely high load, which can hardly occur in a real-life computer. And even that voltage did not violate the limit anyway.
Output Voltage Ripple
The three main voltages fit within the permissible limits in terms of high-frequency pulsation.
This PSU is cooled by a 140mm fan from Yate Loon. Despite the transparent impeller, the fan has no highlighting.
The fan keeps a constant speed of 900 RPM until a load of 450 watts. Then it begins to accelerate, reaching a maximum of 1600 RPM. So, the HK901-11PEP is a quiet power supply. It does not get very hot at work, which indicates high efficiency.
Efficiency and Power Factor
Indeed, the PSU is over 90% efficient at the peak and 87% efficient at full load. It is now clear how the developers managed to ensure proper cooling of this high-density PSU using modest heatsinks. The PSU just doesn’t generate too much heat!
The standby source copes with its job superbly. Its output voltage is never lower than 5 volts even under full load.
The Huntkey HK901-11PEP is good. It has a handy selection of cables and connectors. It is stable, efficient and quiet. Thus, it is going to be a good choice for a top-end gaming machine or a workstation. The downside is that it was not stable with my UPS that has a non-sinusoid output voltage. But considering that the pair switched to the batteries normally, I don’t expect any problems with UPSes that produce a sinusoid output voltage.