[nextpage title=”Introduction”]

Andyson is another OEM manufacturer that is trying to enter the retail market using its own brand. Let’s take a look at its Nuclear 850 power supply.

There are two big issues with the Nuclear series from Andyson. First, all models from this series use a model number 100 W above their labeled wattage. The Nuclear 850 is officially a 750 W unit, which is also true for the other members of this series: the Nuclear 950 is an 850 W unit, the Nuclear 1150 is a 1,050 W unit, and the Nuclear 1300 is a 1,200 W unit. That alone would make us discredit Andyson as a serious company. What is strange, however, is that the Nuclear 850 is capable of delivering 850 W, as we will see in our tests. Therefore, the manufacturer could either officially upgrade this unit as an 850 W product or label it as Nuclear 750.

The second big issue with this unit is that it carries an illegal 80 Plus Bronze certification. Although this unit can provide high efficiency, it was not certified by Ecos Consulting; therefore, the use of the 80 Plus logo and designation is illegal. Unfortunately some companies try to fly under the radar, especially if they don’t have any retail presence in the United States. We’ve reported this problem to Ecos Consulting, which has already notified Andyson, and we hope they will get the official 80 Plus Bronze certification soon.

Usually, we see these problems with low-end power supplies that carry fake wattage and lousy performance, which is not the case with this unit. So, why a manufacturer would hurt itself when the situation is completely avoidable is beyond our comprehension. This only reinforces our understanding that most OEM manufacturers when going to the retail market have no clue what marketing really means.

The Nuclear 850 and the Ultra LSX 750 use the same platform, with the only internal difference being the configuration of the +12 V transistors. Externally, however, they are different, since the LSX 750 doesn’t have a modular cabling system and the Nuclear 850 does.

Andyson Nuclear 850 power supplyFigure 1: Andyson Nuclear 850 power supply

Andyson Nuclear 850 power supplyFigure 2: Andyson Nuclear 850 power supply

The Andyson Nuclear 850 is 6.5” (165 mm) deep, using a 135 mm ball bearing fan on its bottom (Young Lin Tech DFB132512H, 1,700 rpm, 91.16 cfm, 36.28 dBA).

This unit has a modular cabling system with six connectors, and three cables are permanently attached to the power supply. This power supply comes with the following cables:

  • Main motherboard cable with a 20/24-pin connector, 22” (56 cm) long, permanently attached to the power supply
  • One cable with two ATX12V connectors that together form an EPS12V connector, 25.2” (64 cm) long, permanently attached to the power supply
  • One cable with one EPS12V connector, 25.2” (64 cm) long, permanently attached to the power supply
  • Two cables, each with two six/eight-pin connectors for video cards, 19.7” (50 cm) to the first connector, 5.9” (15 cm) between connectors, modular cabling system
  • Two cables, each with four SATA power connectors, 19.7” (50 cm) to the first connector, 5.9” (15 cm) between connectors, modular cabling system
  • Two cables, each with four standard peripheral power connectors and one floppy disk drive power connector, 19.7” (50 cm) to the first connector, 5.9” (15 cm) between connectors

All wires are 18 AWG, which is the correct gauge to be used.

The cable configuration is perfect for a 750 W product, but if it were labeled as 850 W we’d like to see two additional video card power connectors in order to allow you to install three video cards without the need for adapters.

Andyson Nuclear 850 power supplyFigure 3: Cables

Let’s now take an in-depth look inside this power supply.

[nextpage title=”A Look Inside the Andyson Nuclear 850″]

We decided to disassemble this power supply to see what it looks like inside, how it is designed, and what components are used. Please read our Anatomy of Switching Power Supplies tutorial to understand how a power supply works and to compare this power supply to others.

In this page we will have an overall look, and then in the following pages we will discuss in detail the quality and ratings of the components used. The printed circuit board and the primary of the Andyson Nuclear 850 is identical to the ones used in the Ultra LSX 750.

Andyson Nuclear 850 power supplyFigure 4: Top view

Andyson Nuclear 850 power supplyFigure 5: Front quarter view

Andyson Nuclear 850 power supplyFigure 6: Rear quarter view

Andyson Nuclear 850 power supplyFigure 7: The printed circuit board

[nextpage title=”Transient Filtering Stage”]

As we have mentioned in other articles and reviews, the first place we look when opening a power supply for a hint about its quality, is its filtering stage. The recommended components for this stage are two ferrite coils, two ceramic capacitors (Y capacitors, usually blue), one metalized polyester capacitor (X capacitor), and one MOV (Metal-Oxide Varistor). Very low-end power supplies use fewer components, usually removing the MOV and the first coil. 

In this power supply, this stage is flawless. It has one X capacitor and two Y capacitors more than the minimum required.

Andyson Nucle
ar 850 power supplyFigure 8: Transient filtering stage (part 1)

Andyson Nuclear 850 power supplyFigure 9: Transient filtering stage (part 2)

In the next page we will have a more detailed discussion about the components used in the Andyson Nuclear 850.

[nextpage title=”Primary Analysis”]

On this page we will take an in-depth look at the primary stage of the Andyson Nuclear 850. For a better understanding, please read our Anatomy of Switching Power Supplies tutorial.

This power supply uses one GBJ1506 rectifying bridge on its primary, which is attached to the same heatsink used by the active PFC transistors. This component supports up to 15 A at 100° C, so in theory, you would be able to pull up to 1,725 W from a 115 V power grid. Assuming 80% efficiency, the bridge would allow this unit to deliver up to 1,380 W without burning itself out. Of course, we are only talking about this component, and the real limit will depend on all the other components in this power supply.

Andyson Nuclear 850 power supplyFigure 10: Rectifying bridge

The active PFC circuit uses two SPW21N50C3 MOSFETs, each supporting up to 21 A at 25° C or up to 13.1 A at 100° C (note the difference temperature makes) in continuous mode, or up to 63 A in pulse mode at 25° C. These transistors present a 190 mΩ resistance when turned on, a characteristic called RDS(on). The lower this number the better, meaning that the transistor will waste less power and the power supply will have a higher efficiency.

Andyson Nuclear 850 power supplyFigure 11: Active PFC transistors

The electrolytic capacitor that filters the output of the active PFC circuit is from Teapo and labeled at 85° C.

In the switching section, another two SPW21N50C3 MOSFETs are used in the traditional two-transistor forward configuration. The specs for these transistors were already published above.

Andyson Nuclear 850 power supplyFigure 12: Switching transistors

The primary is controlled by the omnipresent CM6800 active PFC/PWM combo controller.

Andyson Nuclear 850 power supplyFigure 13: Active PFC/PWM combo controller

Let’s now take a look at the secondary of this power supply.

[nextpage title=”Secondary Analysis”]

The Andyson Nuclear 850 uses a synchronous design, meaning that the rectifiers were replaced with transistors in order to increase efficiency. On top of that, this unit uses a DC-DC design in its secondary, meaning that this power supply is basically a +12 V unit with two smaller power supplies connected to the +12 V output in order to generate the +5 V and +3.3 V outputs. This design also improves efficiency.

The +12 V output uses four ME80N08 MOSFETs, two for the direct rectification and two for the “freewheeling” part of the rectification. Each transistor can handle up to 80 A at 25° C in continuous mode or up to 300 A at 25° C in pulse mode, with a maximum RDS(on) of 8.7 mΩ. Unfortunately, the manufacturer doesn’t state the current limits at 100° C. Here lies the only difference between the Nuclear 850 and the Ultra LSX 750: In the Ultra model there are three IRFB320s here.

Andyson Nuclear 850 power supplyFigure 14: +12 V transistors

As explained, the +5 V and +3.3 V outputs are generated using two DC-DC converters, each one available as a small daughterboard attached to the main printed circuit board. Each converter is controlled by an APW7073 PWM controller and four ME75N03 MOSFET transistors, each one able to deliver up to 86 A at 25° C or up to 70 A at 70° C in continuous mode, or up to 20 A at 25° C in pulse mode, with a maximum RDS(on) of 9 mΩ.

Andyson Nuclear 850 power supplyFigure 15: One of the DC-DC converters

Andyson Nuclear 850 power supplyFigure 16: One of the DC-DC converters

This power supply uses a PS113 monitoring integrated circuit, which only supports over voltage (OVP) and under voltage (UVP) protections. The manufacturer advertises this unit as having four +12 V rails, but this does not correspond to the truth. Since the protection circuit does not have over current protection, this unit has a single rail. As you can see in Figure 17, the PS113 integrated circuit could be replaced with a bigger integrated circuit, probably featuring this protection – only then would this unit have four +12 V rails.

Andyson Nuclear 850 power s
upplyFigure 17: Monitoring circuit

The electrolytic capacitors available in the secondary are also from Teapo and labeled at 105° C.[nextpage title=”Power Distribution”]

In Figure 18, you can see the power supply label containing all the power specs.

Andyson Nuclear 850 power supplyFigure 18: Power supply label

This power supply is sold as having four +12 V rails, but this is false; this unit has a single +12 V rail. In order to create virtual +12 V rails, each rail must have its own over current protection circuit. Since this power supply doesn’t have over current protection (OCP), there is no protection separating each rail and, therefore, there is only one +12 V rail. As shown in the previous page, the printed circuit board of the power supply allows the installation of a bigger monitoring integrated circuit, which would probably bring the missing four OCP channels. Click here to understand more about this subject.

How much power can this unit really deliver? Let’s check it out.

[nextpage title=”Load Tests”]

We conducted several tests with this power supply, as described in the article Hardware Secrets Power Supply Test Methodology.  

First we tested this power supply with five different load patterns, trying to pull around 20%, 40%, 60%, 80%, and 100% of its labeled maximum capacity (actual percentage used listed under “% Max Load”), watching the behavior of the reviewed unit under each load. Then we decided to add a sixth load for 850 W. We were very curious to see if this unit would be able to deliver 850 W since its name is “Nuclear 850.” In the table below, we list the load patterns we used and the results for each load.

If you add all the powers listed for each test, you may find a different value than what is posted under “Total” below. Since each output can have a slight variation (e.g., the +5 V output working at +5.10 V), the actual total amount of power being delivered is slightly different than the calculated value. In the “Total” row, we are using the real amount of power being delivered, as measured by our load tester.

The +12VA and +12VB inputs listed below are the two +12 V independent inputs from our load tester. During this test both were connected to the power supply single +12 V rail (the EPS12V connector was installed on the +12VB input).

Input Test 1 Test 2 Test 3 Test 4 Test 5 Test 6
+12VA 5 A (60 W) 11 A (132 W) 16 A (192 W) 22 A (264 W) 27 A (324 W) 31 A (384 W)
+12VB 5 A (60 W) 10 A (120 W) 16 A (192 W) 21 A (252 W) 27 A (324 W) 31 A (384 W)
+5V 2 A (10 W) 4 A (20 W) 6 A (30 W) 8 A (40 W) 10 A (50 W) 11 A (70 W)
+3.3 V 2 A (6.6 W) 4 A (13.2 W) 6 A (19.8 W) 8 A (26.4 W) 10 A (33 W) 11 A (46.2 W)
+5VSB 1 A (5 W) 1.5 A (7.5 W) 2 A (10 W) 2.5 A (12.5 W) 3 A (15 W) 3 A (15 W)
-12 V 0.5 A (6 W) 0.5 A (6 W) 0.5 A (6 W) 0.5 A (6 W) 0.5 A (6 W) 0.5 A (6 W)
Total 149.3 W 301.5 W 452.5 W 614.5 W 750.3 W 849.5 W
% Max Load 19.9% 40.2% 60.3% 81.9% 100.0% 113.3%
Room Temp. 45.3° C 45.2° C 45.9° C 47.4° C 45.8° C 49.2° C
PSU Temp. 45.6° C 46.6° C 47.6° C 49.6° C 52.0° C 47.0° C
Voltage Regulation Pass Pass Pass Pass Pass Pass
Ripple and Noise Pass Pass Pass Pass Pass Pass
AC Power 179.8 W 349.4 W 524.6 W 724.0 W 903.0 W 1047.0 W
Efficiency 83.0% 86.3% 86.3% 84.9% 83.1% 81.1%
AC Voltage 117.2 V 115.9 V 114.4 V 112.4 V 110.1 V 105.3 V
Power Factor 0.971 0.987 0.992 0.995 0.996 0.997
Final Result Pass Pass Pass Pass Pass Pass

The Nuclear 850 is a nice 750 W power supply, as you can see, providing efficiency between 83% and 86%, easily conforming with the 80 Plus Bronze certification at high temperatures. It is important to understand that presenting efficiency compatible with any 80 Plus certification level does not grant the manufacturer the right to say the unit is 80 Plus-certified; the company must pay the certification fee and have the power supply tested. At 850 W, however, efficiency dropped to 81%.

Voltage regulation was very good, with all positive voltages within 3% of their nominal values, except for the +5 V output during test five (but it was still inside the proper range; the -12 V output was outside this tighter regulation during tests one and two but was still inside the proper range as well). This means that voltages were closer to their nominal values than required by the ATX12V specification, which says positive voltages must be within 5% of their nominal values and negative voltages must be within 10% of their nominal values. During the 850 W test, the +3.3 V output was at +3.20 V and the +5 V was at +4.78 V, values outside this tighter 3% tolerance but still inside the 5% range allowed by the ATX12V specification.

Noise and ripple levels were always very low. Below you can see the results for the power supply outputs during tests number five and six. The maximum allowed is 120 mV for +12 V and -12 V outputs, and 50 mV for +5 V, +3.3 V and +5VSB outputs. All values are peak-to-peak figures.

Andyson Nuclear 850 power supplyFigure 19: +12VA input from load tester during test five at 750.3 W (23.6 mV)

Andyson Nuclear 850 power supplyFigure 20: +12VB input from load tester during test five at 750.3 W (30.4 mV)

Andyson Nuclear 850 power supplyFigure 21: +5V rail during test five at 750.3 W (17.2 mV)

Andyson Nuclear 850 power supplyFigure 22: +3.3 V rail during test five at 750.3 W (19.8 mV)

Andyson Nuclear 850 power supplyFigure 23: +12VA input from load tester during test six at 849.5 W (27.8 mV)

Andyson Nuclear 850 power supplyFigure 24: +12VB input from load tester during test six at 849.5 W (37.2 mV)

Andyson Nuclear 850 power supplyFigure 25: +5V rail during test six at 849.5 W (20.6 mV)

Andyson Nuclear 850 power supplyFigure 26: +3.3 V rail during test six at 849.5 W (22.4 mV)

Let’s see if we can pull more than 850 W from this unit.

[nextpage title=”Overload Tests”]

Below you can see the maximum we could pull from this power supply. We couldn’t pull more than that because the power supply shut down, showing that its protections were working just fine.

Input Overload Test
+12VA 32 A (384 W)
+12VB 32 A (384 W)
+5V 14 A (70 W)
+3.3 V 14 A (46.2 W)
+5VSB 3 A (15 W)
-12 V 0.5 A (6 W)
Total 883.2 W
% Max Load 117.8%
Room Temp. 48.1° C
PSU Temp. 56.6° C
AC Power 1,092 W
Efficiency 80.9%
AC Voltage 107.8 V
Power Factor 0.997

[nextpage title=”Main Specifications”]

The specs of the Andyson Nuclear 850 include:

  • Standards: ATX12V 2.3 and EPS12V 2.92
  • Nominal labeled power: 750 W
  • Measured maximum power: 883.2 W at 48.1° C ambient
  • Labeled efficiency: Above 85% at typical load (i.e., 50% load, 375 W)
  • Measured efficiency: Between 83.1% and 86.3%, at 115 V (nominal, see complete results for actual voltage)
  • Active PFC: Yes
  • Modular Cabling System: Yes
  • Motherboard Power Connectors: One 20/24-pin connector, two ATX12V connectors that together form an EPS12V connector, and one EPS12V connector, permanently attached to the power supply
  • Video Card Power Connectors: Four six/eight-pin connectors on two cables
  • SATA Power Connectors: Eight on two cables
  • Peripheral Power Connectors: Eight on two cables
  • Floppy Disk Drive Power Connectors: Two on two cables
  • Protections (as listed by the manufacturer): Over voltage (OVP), under voltage (UVP), over current (OCP), over power (OPP), and short-circuit (SCP) protections
  • Are the above protections really available? No, the unit doesn’t have over current protection (OCP).
  • Warranty: NA
  • More Information: https://www.andysonpower.com
  • Average Price in the US: We couldn’t find this product being sold in the US on the day we published this review.

[nextpage title=”Conclusions”]

The Andyson Nuclear 850 is a very nice 750 W power supply. Thanks to its synchronous rectification and DC-DC design, it presents very good efficiency, with low noise and ripple levels and voltages closer to their nominal values than required most of the time. The cable configuration is perfect for a 750 W product.

Why the manufacturer is selling this unit as “Nuclear 850” is a mystery to us. It should either change the name of the product to “Nuclear 750” or change the official wattage of the unit to 850 W, since it can deliver 850 W at high temperatures. Although this unit, if tested as a 750 W product, really presents performance compatible with the 80 Plus Bronze level, the manufacturer cannot claim this unit as being 80 Plus Bronze-certified, as it is currently doing. To have the right to use the 80 Plus name and logo, the manufacturer must pay a certification and licensing fee and send the unit to be tested.

The Nuclear 850 is sold as having four virtual +12 V rails, but since this unit doesn’t have over current protection (OCP) on each rail, it actually uses a single-rail design.

This only reinforces our understanding that most OEM manufacturers, when going to the retail market, have no clue what marketing really means. Andyson is hurting itself with its own blindness; the product is excellent on its own, and lying is not necessary.