The Xigmatek Tauro power supply series is comprised of 400 W, 500 W, 600 W, and 700 W models, with the 80 Plus Bronze certification. Today we are testing the 700 W model to see if it is a good product. Check it out.
The Xigmatek Tauro 700 W is 6.2” (158 mm) deep, using a 135 mm sleeve-bearing fan on its bottom (Xigmatek DFS132512H, which is actually manufactured by Young Lin Tech).
The reviewed power supply doesn’t have a modular cabling system. All cables are protected with nylon sleeves, but only the sleeve used on the main motherboard cable comes from inside the unit. This power supply comes with the following cables:
- Main motherboard cable with a 20/24-pin connector, 20.5” (52 cm) long
- One cable with two ATX12V connectors that together form an EPS12V connector, 24.6” (62 cm) long
- Two cables, each with two six/eight-pin connectors for video cards, 20.5” (52 cm) to the first connector, 5.9” (15 cm) between connectors
- Two cables, each with four SATA power connectors, 16.5” (42 cm) to the first connector, 5.9” (15 cm) between connectors
- One cable with four standard peripheral power connectors and one floppy disk drive power connector, 16.5” (42 cm) to the first connector, 5.9” (15 cm) between connectors
The main motherboard cable and the EPS12V/ATX12V cable use thicker 16 AWG wires, while the other wires have the minimum recommended gauge (18 AWG). The number of connectors is perfect.
Let’s now take an in-depth look inside this power supply.
[nextpage title=”A Look Inside the Xigmatek Tauro 700 W”]
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.
On 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.
[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 the transient filtering stage, this power supply is flawless, with one X capacitor more than the minimum required.
On the next page, we will have a more detailed discussion about the components used in the Xigmatek Tauro 700 W.
[nextpage title=”Primary Analysis”]
On this page we will take an in-depth look at the primary stage of the Xigmatek Tauro 700 W. For a better understanding, please read our “Anatomy of Switching Power Supplies” tutorial.
This power supply uses one BU1506 rectifying bridge, which is attached to an individual heatsink. This bridge supports up to 15 A at 80° 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 particular component. The real limit will depend on all the components combined in this power supply.
The active PFC circuit uses two SPW24N60C3 MOSFETs, each supporting up to 24.3 A at 25° C or 15.4 A at 100° C in continuous mode (see the di
fference temperature makes) or 72.9 A at 25° C in pulse mode. These transistors present a maximum 160 mΩ resistance when turned on, a characteristic called RDS(on). The lower the number the better, meaning that the transistor will waste less power, and the power supply will have a higher efficiency.
The output of the active PFC circuit is filtered by one 390 µF x 420 V electrolytic capacitor from Teapo, labeled at 85° C.
In the switching section, another two SPW24N60C3 MOSFETs are employed using the traditional two-transistor forward configuration. The specifications for these transistors were already discussed above.
The primary is managed by the famous CM6806 active PFC/PWM combo controller.
Let’s now take a look at the secondary of this power supply.
[nextpage title=”Secondary Analysis”]
The Xigmatek Tauro 700 W uses a DC-DC design in its secondary. This means that the power supply is basically a +12 V unit, with the +5 V and +3.3 V outputs produced by two smaller power supplies connected to the main +12 V rail. Also, the +12 V output uses a synchronous design, where the rectifiers were replaced with MOSFETs. Both designs are used to increase efficiency.
The +12 V output uses three IRFB3206GPBF MOSFETs, each supporting up to 120 A at 25° C in continuous mode or 840 A at 25° C in pulse mode, with a maximum RDS(on) of 3 mΩ.
The DC-DC converters are located on two individual daughterboards. Each converter is managed by an APW7073 PWM controller, using four QM3004D MOSFETs, each supporting up to 55 A at 25° C or 45 A at 100° C in continuous mode or 110 A at 25° C in pulse mode, with a maximum RDS(on) of 14 mΩ.
This power supply uses a PS223 monitoring integrated circuit, which supports over voltage (OVP), under voltage (UVP), and over current (OCP) protections. Even though this chip provides two +12 V over current channels, the manufacturer decided to configure this unit as a single-channel model.
The electrolytic capacitors that filter the outputs are from Teapo and JunFu and labeled at 105° C, as usual.
[nextpage title=”Power Distribution”]
In Figure 17, you can see the power supply label containing all the power specs.
As you can see, this unit has a single +12 V rail, so there is not much to talk about here.
How much power can this unit really deliver? Let’s find 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. 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 inputs were connected to the power supply’s single +12 V rail. (The power supply’s EPS12V connector was installed on the +12VB input of the load tester.)
|Input||Test 1||Test 2||Test 3||Test 4||Test 5|
|+12VA||4.5 A (54 W)||9.5 A (114 W)||14.5 A (174 W)||19 A (228 W)||25 A (300 W)|
|+12VB||4.5 A (54 W)||9.5 A (114 W)||14.5 A (174 W)||19 A (228 W)||25 A (300 W)|
|+5 V||1 A (5 W)||4 A (20 W)||6 A (30 W)||8 A (40 W)||10 A (50 W)|
|+3.3 V||1 A (3.3 W)||4 A (13.2 W)||6 A (19.8 W)||8 A (26.4 W)||10 A (33 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)|
|-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)|
|Total||137.8 W||278.2 W||417.7 W||543.4 W||703.4 W|
|% Max Load||19.7%||39.7%||59.7%||77.6%||100.5%|
|Room Temp.||45.0° C||45.2° C||46.3° C||47.5° C||45.4° C|
|PSU Temp.||45.2° C||45.8° C||47.3° C||48.5° C||49.2° C|
|Ripple and Noise||Pass||Pass||Pass||Pass||Pass|
|AC Power||170.8 W||327.2 W||489.
|645.0 W||857.0 W|
|AC Voltage||114.4 V||113.1 V||109.1 V||108.4 V||106.2 V|
The 80 Plus Bronze certification guarantees minimum efficiencies of 82% at 20% and full loads, and 85% at 50% load. In our tests, the Xigmatek Tauro 700 W presented 80.7% efficiency at 20% load. Unfortunately, we see this happening time and time again, as the 80 Plus tests are conducted at 23° C and we test power supplies between 45° C and 50° C, and efficiency drops with temperature.
All voltages were closer to their nominal values during all tests (3% voltage regulation), except the +5VSB output during test five, which was at +4.82 V, still inside the allowed range. The ATX12V specification states that positive voltages must be within 5% of their nominal values, and negative voltages must be within 10% of their nominal values.
Let’s discuss the ripple and noise levels on the next page.
[nextpage title=”Ripple and Noise Tests”]
Voltages at the power supply outputs must be as “clean” as possible, with no noise or oscillation (also known as “ripple”). The maximum ripple and noise levels allowed are 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. We consider a power supply as being top-notch if it can produce half or less of the maximum allowed ripple and noise levels.
The Xigmatek Tauro 700 W provided low ripple and noise levels, as you can see below.
|Input||Test 1||Test 2||Test 3||Test 4||Test 5|
|+12VA||13.4 mV||15.0 mV||19.4 mV||24.6 mV||33.4 mV|
|+12VB||13.2 mV||14.6 mV||18.0 mV||23.0 mV||31.8 mV|
|+5 V||10.6 mV||13.0 mV||14.6 mV||16.6 mV||22.8 mV|
|+3.3 V||13.2 mV||15.4 mV||17.0 mV||21.0 mV||27.2 mV|
|+5VSB||15.2 mV||18.2 mV||25.6 mV||33.4 mV||45.4 mV|
|-12 V||7.0 mV||9.4 mV||11.2 mV||14.6 mV||18.4 mV|
Below you can see the waveforms of the outputs during test five.
[nextpage title=”Overload Tests”]
Below you can see the maximum we could pull from this power supply. The objective of this test is to see if the power supply has its protection circuits working properly. This unit passed this test, at it shut down when we tried to pull more than listed in the table below. Noise and ripple levels were still low, and voltages were still within 3% of their nominal values.
|+12VA||30 A (360 W)|
|+12VB||30 A (360 W)|
|+5 V||10 A (50 W)|
|+3.3 V||10 A (33 W)|
|+5VSB||3 A (15 W)|
|-12 V||0.5 A (6 W)|
|% Max Load||116.3%|
|Room Temp.||49.4° C|
|PSU Temp.||49.2° C|
|AC Power||1,014 W|
|AC Voltage||105.8 V|
[nextpage title=”Main Specifications”]
The main specifications for the Xigmatek Tauro 700 W power supply include:
- Standards: NA
- Nominal labeled power: 700 W at 50° C
- Measured maximum power: 814.4 W at 49.4° C
- Labeled efficiency: Above 85%, 80 Plus Bronze certification, 82% minimum at light (i.e., 20%) and full loads, 85% minimum at typical (i.e., 50%) load
- Measured efficiency: Between 80.7% and 85.4%, at 115 V (nominal, see complete results for actual voltage)
- Active PFC: Yes
- Modular Cabling System: No
- Motherboard Power Connectors: One 20/24-pin connector and two ATX12V connectors that together form an EPS12V connector
- Video Card Power Connectors: Four six/eight-pin connectors on two cables
- SATA Power Connectors: Eight on two cables
- Peripheral Power Connectors: Four on one cable
- Floppy Disk Drive Power Connectors: One
- Protections (as listed by the manufacturer): Over voltage (OVP), under voltage (UVP), over current (OCP), over power (OPP), over temperature (OTP), and short-circuit (SCP)
- Are the above protections really available? Yes.
- Warranty: Three years
- Real Manufacturer: Andyson
- More Information: https://www.xigmatek.com
- MSRP in the U.S.: USD 99.00
The Xigmatek Tauro 700 W is a good product for its target audience, with efficiency up to 85%, very good voltage regulation, and low ripple and noise levels. The cable configuration is great for a 700 W product. Efficiency at light load (i.e., 20% load), however, could be better. This unit faces tough competition. The Thermaltake TR2 700 W, which also has the 80 Plus Bronze certification and got great results in our tests, costs USD 90. The In Win GreenMe 750 W has a suggested price of USD 100. We know that USD 99 is the manufacturer suggested retail price, and resellers usually sell for less than the MSRP. The Tauro 700 W is a good pick if it is offered for USD 90 or less. Otherwise, there are better options on the market.