Ultra X4 850 W Power Supply Review
By Gabriel Torres on October 19, 2009


Introduction

Hardware Secrets Silver AwardUltra is a traditional power supply manufacturer and the first to come with the modular cabling system idea (which led the company to sue all manufacturers that launched power supplies with a modular cabling system, including Antec, Thermaltake, FSP, CWT, Seasonic and Corsair, just to name a few). Today they are launching a new series called X4 featuring a complete modular cabling system and single-rail design. Let’s see if the 850 W model from this new series is a good buy.

Power supplies from X4 series are manufactured by Andyson. The only other power supply from Andyson that we ever tested was BFG ES-800 (note that BFG uses other manufacturers besides Andyson).

Ultra X4 850 W power supply
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Figure 1: Ultra X4 850 W power supply.

Ultra X4 850 W power supply
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Figure 2: Ultra X4 850 W power supply.

Ultra X4 850 W is a small 850 W unit, being 6 19/64” (160 mm) deep, using a 135 mm fan on its bottom and featuring active PFC, of course.

As mentioned, Ultra X4 has a fully modular cabling system, meaning that even the main motherboard cable is removable. The cables included are:

All wires are 18 AWG, which is the correct gauge to be used, except the wires on the main motherboard cable, which are thicker (16 AWG).

As you can see Ultra X4 850 W comes with six individual power connectors for video cards, and they can be all used together. This means Ultra X4 850 W supports SLI/CrossFire configurations with three video cards that required two auxiliary power connectors each. This is a perfect configuration for an 850 W product.

Ultra X4 850 W power supply
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Figure 3: Cables.

Now let’s take an in-depth look inside this power supply.

A Look Inside The Ultra X4 850 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.

This page will be an overview, and then in the following pages we will discuss in detail the quality and ratings of the components used.

Ultra X4 850 W power supply
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Figure 4: Overall look.

Ultra X4 850 W power supply
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Figure 5: Overall look.

Ultra X4 850 W power supply
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Figure 6: Overall look.

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.

This stage is flawless, with two Y capacitors and one X capacitor (plus another X capacitor after the rectification bridge) more than the minimum required.

Ultra X4 850 W power supply
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Figure 7: Transient filtering stage (part 1).

Ultra X4 850 W power supply
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Figure 8: Transient filtering stage (part 2).

In the next page we will have a more detailed discussion about the components used in the Ultra X4 850 W.

Primary Analysis

On this page we will take an in-depth look at the primary stage of Ultra X4 850 W. For a better understanding, please read our Anatomy of Switching Power Supplies tutorial.

This power supply uses one GBJ2506 rectifying bridge in its primary, which can deliver up to 25A at 100° C  if a heatsink is used, which is the case. This component is clearly overspec’ed: at 115 V this unit would be able to pull up to 2,875 W from the power grid; assuming 80% efficiency, the bridge would allow this unit to deliver up to 2,300 W without burning this component. Of course we are only talking about this component and the real limit will depend on all other components from the power supply.

Ultra X4 850 W power supply
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Figure 9: Rectifying bridge.

On the active PFC circuit two SPW21N50C3 power MOSFET transistors are used, each one capable of delivering up to 21 A at 25° C or 13.1 A at 100° C in continuous mode (note the difference temperature makes), or up to 63 A in pulse mode at 25° C. These transistors present a resistance of 190 mΩ when turned on, a characteristic called RDS(on). This number indicates the amount of power that is wasted, so the lower this number the better, as less power will be wasted thus increasing efficiency.

Ultra X4 850 W power supply
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Figure 10: Active PFC transistors.

This power supply uses a Japanese capacitor from Matsushita (Panasonic) labeled at 85° C to filter the output from the active PFC circuit.

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

Ultra X4 850 W power supply
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Figure 11: Switching transistors.

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

Ultra X4 850 W power supply
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Figure 12: PFC/PWM combo controller.

Now let’s take a look at the secondary of this power supply.

Secondary Analysis

This power supply has nine Schottky rectifiers attached to its secondary heatsink.

The maximum theoretical current each line can deliver is given by the formula I / (1 - D), where D is the duty cycle used and I is the maximum current supported by the rectifying diode. Just as an exercise, we can assume a typical duty cycle of 30%.

The +12 V output is produced by four ESAE83-004 Schottky rectifiers, each one providing up to 60 A (30 A per internal diode at 110° C, maximum voltage drop of 0.55 V). This gives us a maximum theoretical current of 171 A or 2,057 W. That is what we call overspecification!

By the way, we are now talking about the voltage drop presented by the rectifiers. This parameter shows how much voltage is wasted by the rectifier. The lower this number is, the better, as less voltage is wasted, increasing efficiency.

The +5 V output is produced by two SPR30L30CT Schottky rectifiers connected in parallel (30 A, 15 A per internal diode at 125° C, typical voltage drop of 0.38 V), giving us a maximum theoretical current of 43 A or 214 W for this output.

The +3.3 V output is produced by another two SPR30L30CT Schottky rectifiers, so the maximum theoretical power this output can deliver is of 141 W.

The ninth rectifier, an STPS20L60CT (20 A total, 10 A per diode at 140° C, maximum voltage drop of 0.56 V), is used by the standby (+5VSB) output.

All these numbers are theoretical. The real amount of current/power each output can deliver is limited by other components, especially by the coils used on each output.

Ultra X4 850 W power supply
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Figure 13: Rectifiers.

The outputs are monitored by a PS232 integrated circuit, which supports the following protections: over current (OCP), under voltage (UVP) and over voltage (OVP). Any other protection that this unit may have is implemented outside this integrated circuit.

Ultra X4 850 W power supply
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Figure 14: Monitoring circuit.

Electrolytic capacitors from the secondary are from Teapo and labeled at 105° C.

Power Distribution

In Figure 15, you can see the power supply label containing all the power specs.

Ultra X4 850 W power supply
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Figure 15: Power supply label.

Since Ultra X4 850 W uses a single-rail design there is not much to talk about here.

Now let’s see if this power supply can really deliver 850 W.

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 how the reviewed unit behaved 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 power listed for each test, you may find a different value than what is posted under “Total” below. Since each output can vary slightly (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. On the “Total” row we are using the real amount of power being delivered, as measured by our load tester.

+12V1 and +12V2 are the two independent +12V inputs from our load tester and during our tests both were connected to the power supply’s single +12 V rail.

Input

Test 1

Test 2

Test 3

Test 4

Test 5

+12V1

6 A (72 W)

13 A (156 W)

20 A (240 W)

25 A (300 W)

29 A (348 W)

+12V2

6 A (72 W)

12 A (144 W)

17 A (204 W)

25 A (300 W)

29 A (348 W)

+5V

2 A (10 W)

4 A (20 W)

6 A (30 W)

8 A (40 W)

16 A (80 W)

+3.3 V

2 A (6.6 W)

4 A (13.2 W)

6 A (19.8 W)

8 A (26.4 W)

16 A (52.8 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

177.6 W

357.4 W

523.8 W

699.7 W

861.0 W

% Max Load

20.9%

42.0%

61.6%

82.3%

101.3%

Room Temp.

45.8° C

46.6° C

49.0° C

48.5° C

48.2° C

PSU Temp.

47.8° C

48.9° C

51.4° C

55.5° C

56.8° C

Voltage Regulation

Pass

Pass

Pass

Pass

Pass

Ripple and Noise

Pass

Pass

Pass

Pass

Pass

AC Power

217.4 W

422.1 W

619.0 W

840.0 W

1065.0 W

Efficiency

81.7%

84.7%

84.6%

83.3%

80.8%

AC Voltage

113.5 V

111.9 V

109.2 V

107.6 V

104.7 V

Power Factor

0.933

0.974

0.984

0.988

0.991

Final Result

Pass

Pass

Pass

Pass

Pass

Ultra X4 850 W presented very good efficiency when delivering between 40% and 80% from its labeled power (between 340 W and 680 W), on the 83%-85% range. At 20% load (170 W) efficiency dropped to 81.7%, still a decent number. When delivering 850 W, it presented 80.8% efficiency, not the best but still above 80%.

There is something really weird about the 80 Plus certification from this power supply. The manufacturer says this unit has the standard 80 Plus certification, what makes sense according to our tests. But at 80 Plus website this unit is listed as 80 Plus Silver with a typical efficiency of 89% and average efficiency of 87%. Probably the sample Ultra sent to 80 Plus was internally different from the product they ended up manufacturing.

Voltages were always inside the maximum allowed (5% tolerance for the positive voltages and 10% for -12 V).

Ripple and noise levels were also below the maximum allowed. You can see the results below for test number five. All values are peak-to-peak figures and the maximum allowed is 120 mV for the +12 V outputs and 50 mV for the +5 V and +3.3 V outputs.

Ultra X4 850 W Power Supply
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Figure 16: +12V1 input from load tester at 861.0 W (88.4 mV).

Ultra X4 850 W Power Supply
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Figure 17: +12V2 input from load tester at 861.0 W (82.6 mV).

Ultra X4 850 W Power Supply
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Figure 18: +5V rail with power supply delivering 861.0 W (20.6 mV).

Ultra X4 850 W Power Supply
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Figure 19: +3.3 V rail with power supply delivering 861.0 W (15.6 mV).

Now let’s see if we could pull more than 850 W from this unit.

Overload Tests

Before overloading power supplies we always test first if the over current protection (OCP) circuit is active and at what level it is configured.

In order to do that we set +5 V and +3.3 V at 1 A and increased the current at the single +12 V rail from the power supply the maximum we could. We pulled 66 A (the maximum our equipment is able to handle) and the unit didn’t shut down, meaning that either OCP is disabled or configured at a value above 66 A.

Then starting from test five we increased currents to the maximum we could with the power supply still running inside ATX specs. The results are below. When we tried to increase one more amp at any output the power supply would shut down, showing that one of its protections was triggered.

The idea behind of overload tests is to see if the power supply will burn/explode and see if the protections from the power supply are working correctly. This power supply passed on this test.

Input

Maximum

+12V1

32 A (384 W)

+12V2

32 A (384 W)

+5V

20 A (100 W)

+3.3 V

20 A (66 W)

+5VSB

3 A (15 W)

-12 V

0.5 A (6 W)

Total

969.4 W

% Max Load

114.0%

Room Temp.

49.2° C

PSU Temp.

59.0° C

AC Power

1,229.0 W

Efficiency

78.9%

AC Voltage

102.4 V

Power Factor

0.992

Main Specifications

Ultra X4 850 W power supply specs include:

* Researched at Tigerdirect.com on the day we published this review.

Conclusions

Ultra X4 850 W is a honest power supply, being able to really deliver 850 W at 48° C. The main advantage of this unit is having six separated video card power cables, allowing you to build an SLI/CrossFire system with up to three high-end video cards without the need of using adapters. The high number of SATA (11) and peripheral (nine) power connectors is also an advantage. Its full modular cabling system is a must for users worried about ventilation and cable organization.

Ultra X4 850 W presents very good efficiency when delivering between 40% and 80% from its labeled power (between 340 W and 680 W), on the 83%-85% range. At 20% load (170 W) efficiency dropped to 81.7%, still a decent number. When delivering 850 W, it presented 80.8% efficiency, not the best but still above 80%.

Voltage regulation and ripple/noise were inside specs, although they were not the best we’ve seen around.

Its price is adequate for a product with these features, but we’d like it more if it cost less. Problem is, if you don’t need the modular cabling system you can buy a Seasonic S12D 850 W for USD 180, which provides a better performance (higher efficiency, voltages closer to their nominal values, lower ripple/noise). And if you want a product with a better performance with a modular cabling system you can pay only USD 10 more and get a Seasonic M12D 850 W or an XFX 850 W.

 

Originally at http://www.hardwaresecrets.com/article/Ultra-X4-850-W-Power-Supply-Review/841


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