Gigabyte AORUS P850W 850W (Page 3 of 4) | Reports

Page 3 - Physical Look - Inside

As always, we opened up our Gigabyte AORUS P850W 850W power supply to take a detailed look at what is going on inside. Please note that doing this at home will void your ten-year warranty, thanks to the warranty seal Gigabyte applied over one of the attachment screws. But for the benefit of you, we cracked ours open so you do not need to, haha. There are no user serviceable parts inside.

Disassembling the Gigabyte AORUS P850W 850W is quite straightforward with the removal of four screws. Our photo above shows an overhead view of its internal components. Its OEM is MEIC, a company that usually makes power bricks. At first glance, the build quality appears to be excellent. There are three main heatsinks inside. One small one and one large one is located on the primary side, while a second medium-sized heatsink resides on the secondary side, all of which are painted black.

A quick tug on the shell, and we got straight to the internal inspection. The transient filter stage is the first input stage of a computer power supply, so we will take a look at that first. Although this is the first power supply we have ever reviewed from Gigabyte, the company has long been known for making quality motherboards and video cards, and this product is no exception. The Gigabyte AORUS P850W 850W has one metal oxide varistor, two metalized polyester X-capacitors, four ceramic Y-capacitors, and two ferrite coils. This is twice times the amount of X and Y capacitors than recommended. Considering how many modern-day PSUs have missing MOVs, I am happy to see it here, as this component is used to stabilize spikes from the AC line. A Champion CM6500 PFC controller and Champion CM03X chip for controlling standby power can be spotted as well.

On the primary side, we can see two Japanese made Nippon Chemi-con capacitors. 100% Japanese made capacitors are specified on the marketing material, so this is to be expected. Our 850W version of Gigabyte's latest AORUS power supply incorporates two 390µF x 400V capacitors in parallel for an equivalent capacitance of 780µF. Both of them are rated at 105c; whereas more value-oriented power supplies usually use 85c rated capacitors.

The active PFC circuit featured on the Gigabyte AORUS P850W 850W uses two Diodes Incorporated GBU1006 glass passivated bridge rectifiers attached to the first heatsink. At 115V, the maximum rectified forward current capacity with heatsink is 10A for each diode, so you can theoretically pull up to 2300W (10A * 2 diodes * 115V) from the bridge rectifier at 100% efficiency -- of course, this is limited by the fact that it is not 100% efficient, and neglects the fact that not every component in the system are able to keep up. Further down the line, on the larger second heatsink, we can see two Alpha & Omega AOT42S60L power transistors. This MOSFET is certified for up to 23A at 100c. These transistors present a maximum resistance of 0.31 ohm when turned on; with a typical resistance of 0.27 ohm at 100c according to the manufacturer's data sheet. This on characteristic is called Static Drain-Source On-Resistance, or commonly abbreviated as RDS(on). The more efficient the component is, the lower the RDS(on) value, since it wastes less power with lower resistance. In the middle of the same unpainted heatsink, we can see a Cree C3D08060A Silicon Carbide Schottky diode. This boost diode is certified for up to 10A at 135c. Two more Alpha & Omega AOT42S60L power MOFSET transistors are used as the main switchers on the AORUS P850W 850W power supply.

On the secondary side, we can see more Japanese made capacitors from Chemi-Con rated at 105c. As with modern high efficiency power supplies, all rectifiers produce the +12V out -- while the +5V and +3.3V outputs are generated from the +12V output using a DC to DC converter within the power supply unit. Four Alpha & Omega AOT2142L MOSFETs are responsible for generating the +12V output. The AOT2142L's rated continuous drain current is 120A at 100c, and a pulsed drain current of 600A. It has a RDS(on) value of 0.0019 ohm maximum and 0.00155 ohm typical. Eight Alpha & Omega AON6360 MOSFETs are responsible for generating the +5V and +3.3V outputs. The AON6360's rated continuous drain current is 59A at 100c and a pulsed drain current of 180A. Drain source voltage is rated at 30V, and a RDS(on) value of 0.003 ohm maximum and 0.0025 ohm typical. Meanwhile, a Weltrend WT7527 monitoring IC provides over/under current and over/under voltage protection. The datasheets for all components mentioned in this review can be found on their respective manufacturer's websites.

At the back, we have a large daughterboard covering the entire rear panel for the modular cable sockets. All modular sockets at the bottom are soldered directly to the main PCB after the secondary stage to reduce power transmission loss. The output connector configuration can be seen on the previous page. Overall, the internal build quality of Gigabyte's AORUS P850W 850W power supply is excellent -- something we would expect from what we have seen from the company in the past, even if this is the first power supply from them. Components are arranged very well for optimal cooling with minimal wires running around inside, and solder points on its black PCB is quite clean in general. I would say the Gigabyte AORUS P850W 850W is generally very good with regards to the selection of components used under the hood; appropriate for its performance class.

Lastly, we see a 135mm fan that provides cooling to the Gigabyte AORUS P850W 850W's internal components. It is connected to the mainboard using a 2-pin connector. A 135mm fan is only marginally smaller than the 140mm maximum you can fit in an ATX power supply, and it is beneficial in most cases in providing lots of airflow at lower speeds for quiet operation. Yate Loon is the fan OEM, with D14BH-12 as the model number, as shown in our photo above. Further research indicates the D14BH-12 is a double ball bearing fan specified at 0.70A for a maximum of speed of 2800 RPM. The rated airflow is 140 CFM at 48.5 dB of noise.


Page Index
1. Introduction, Packaging, Specifications
2. Physical Look - Outside
3. Physical Look - Inside
4. Minor Tests and Conclusion