Ultra X4 500 W Power Supply Review
By Gabriel Torres on November 20, 2009


Introduction

Hardware Secrets Golden Award

Ultra has recently launched a new power supply series, X4, with seven models featuring a complete modular cabling system and single-rail design. We’ve already reviewed the 850 W model from this series and now we are going to dissect their 500 W version.

Power supplies from X4 series are manufactured by Andyson.

Ultra X4 500 W power supply
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Figure 1: Ultra X4 500 W power supply.

Ultra X4 500 W power supply
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Figure 2: Ultra X4 500 W power supply.

Ultra X4 500 W is 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).

The number of cables and connectors is perfect for a 500 W product.

Ultra X4 500 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 500 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 500 W power supply
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Figure 4: Overall look.

Ultra X4 500 W power supply
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Figure 5: Overall look.

Ultra X4 500 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 500 W power supply
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Figure 7: Transient filtering stage (part 1).

Ultra X4 500 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 500 W.

Primary Analysis

On this page we will take an in-depth look at the primary stage of Nexus RX-6300. For a better understanding, please read our Anatomy of Switching Power Supplies tutorial.

This power supply uses one GBU1006 rectifying bridge in its primary, which can deliver up to 10 A at 100° C if a heatsink is used, which is the case, or only 3.2 A if a heatsink is not used. This component is clearly overspec’ed: at 115 V this unit would be able to pull up to 1,150 W from the power grid; assuming 80% efficiency, the bridge would allow this unit to deliver up to 920 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 500 W power supply
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Figure 9: Rectifying bridge.

Ultra X4 500 W uses only one transistor on its active PFC circuit instead of two. An SPW24N60C3 power MOSFET transistors is used, capable of delivering up to 24.3 A at 25° C or 15.4 A at 100° C in continuous mode (note the difference temperature makes), or up to 72.9 A in pulse mode at 25° C, with a resistance of 160 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.

This power supply uses a Taiwanese capacitor from Teapo labeled at 85° C to filter the output from the active PFC circuit. Interesting enough the 850 W model uses a Japanese capacitor here.

In the switching section, two STP20NM50FP power MOSFET transistors are used on the traditional two-transistor forward configuration, each one supporting up to 20 A at 25° C or up to 12.6 A at 100° C in continuous mode, or up to 80 A at 25° C in pulse mode, with an RDS(on) of 250 mΩ.

Ultra X4 500 W power supply
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Figure 10: One of the switching transistors, active PFC diode and active PFC transistor.

The primary is controlled by a tiny version of the famous CM6800 PFC/PWM combo controller.

Ultra X4 500 W power supply
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Figure 11: PFC/PWM combo controller.

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

Secondary Analysis

This power supply has five 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 two 40CPQ060 Schottky rectifiers, each one providing up to 40 A (20 A per internal diode at 120° C, maximum voltage drop of 0.68 V). This gives us a maximum theoretical current of 57 A or 686 W.

The +5 V output is produced by one STPS40L45CW Schottky rectifier (40 A, 20 A per internal diode at 130° C, maximum voltage drop of 0.49 V), giving us a maximum theoretical current of 29 A or 143 W for this output.

The +3.3 V output is produced by another STPS40L45CW Schottky rectifier, so the maximum theoretical power this output can deliver is of 94 W.

The fifth 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 500 W power supply
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Figure 12: Rectifiers.

The outputs are monitored by a PS223 integrated circuit, which supports the following protections: over current (OCP), under voltage (UVP), over voltage (OVP) and over temperature (OTP, not implemented on this power supply). Any other protection that this unit may have is implemented outside this integrated circuit.

Ultra X4 500 W power supply
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Figure 13: Monitoring circuit.

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

Power Distribution

In Figure 14, you can see the power supply label containing all the power specs.

Ultra X4 500 W power supply
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Figure 14: Power supply label.

This power supply uses a single-rail design, so there is not much to talk about here.

Now let’s see if this power supply can really deliver 500 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.

The +12V1 and +12V2 inputs listed below are the two +12 V independent inputs from our load tester. During this test both were connected to the single +12 V rail from this power supply.

Input

Test 1

Test 2

Test 3

Test 4

Test 5

+12V1

4 A (48 W)

7 A (84 W)

11 A (132 W)

14.5 A (174 W)

18 A (216 W)

+12V2

3 A (36 W)

7 A (84 W)

10 A (120 W)

14 A (168 W)

18 A (216 W)

+5V

1 A (5 W)

2 A (10 W)

4 A (20 W)

5 A (25 W)

6 A (30 W)

+3.3 V

1 A (3.3 W)

2 A (6.6 W)

4 A (13.2 W)

5 A (16.5 W)

6 A (19.8 W)

+5VSB

1 A (5 W)

1 A (5 W)

1.5 A (7.5 W)

2 A (10 W)

2.5 A (12.5 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

105.4 W

195.4 W

304.2 W

397.3 W

507.6 W

% Max Load

21.1%

39.1%

60.8%

79.5%

101.5%

Room Temp.

46.5° C

46.5° C

46.1° C

47.2° C

48.5° C

PSU Temp.

48.6° C

49.1° C

49.2° C

50.0° C

51.8° C

Voltage Stability

Pass

Pass

Pass

Pass

Pass

Ripple and Noise

Pass

Pass

Pass

Pass

Pass

AC Power

127.1 W

227.6 W

358.7 W

472.6 W

618.0 W

Efficiency

82.9%

85.9%

84.8%

84.1%

82.1%

AC Voltage

114.0 V

112.4 V

110.8 V

109.9 V

108.3 V

Power Factor

0.984

0.960

0.961

0.966

0.971

Final Result

Pass

Pass

Pass

Pass

Pass

Ultra X4 500 W can really deliver its labeled power at 48.5° C.

Efficiency was very good when delivering between 40% and 80% from its labeled power (between 200 W and 400 W), on the 84%-86% range. At 20% load (100 W) efficiency dropped to 82.9%, still a decent number. When delivering 500 W, it presented 82.1% efficiency, not the best but still above 80%.

This unit is 80 Plus Bronze certified and it could really delivered its promised efficiency at high temperatures.

Voltage regulation was another highlight from this product, with all voltages within 3% from their nominal values, including the -12 V output, which doesn’t like to stay that close to its nominal number. Translation: voltages closer to their nominal values than required (ATX specification allows voltages to be up to 5% from their nominal values; 10% for -12 V).

Ripple and noise levels were also very low. 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 500 W power supply
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Figure 15: +12V1 input from load tester at 507.6 W (42.2 mV).

Ultra X4 500 W power supply
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Figure 16: +12V2 input from load tester at 507.6 W (44 mV).

Ultra X4 500 W power supply
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Figure 17: +5V rail with power supply delivering 507.6 W (21.2 mV).

Ultra X4 500 W power supply
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Figure 18: +3.3 V rail with power supply delivering 507.6 W (23.2 mV).

Now let’s see if we could pull more than 500 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. The power supply shut down when we tried to pull 40 A from its +12 V rail.

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

19 A (228 W)

+12V2

19 A (228 W)

+5V

9 A (45 W)

+3.3 V

9 A (29.7 W)

+5VSB

2.5 A (30 W)

-12 V

0.5 A (6 W)

Total

554.9 W

% Max Load

111.0%

Room Temp.

49.6° C

PSU Temp.

54.9° C

AC Power

691.0 W

Efficiency

80.3%

AC Voltage

106.4 V

Power Factor

0.975

Main Specifications

Ultra X4 500 W power supply specs include:

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

Conclusions

Ultra X4 500 W is a very good 500 W power supply, being able to really deliver 500 W at very high temperatures, efficiency between 82% and 86%, voltages very close to their nominal values and very little noise and ripple. The full modular cabling system is a very nice feature and it comes with the correct number of cables for a 500 W product.

The only negative thing we could say about Ultra X4 500 W is its price: costing USD 100 it is one of the most expensive 500 W power supplies around. For this price you can get a 750 W power supply like Seventeam ST-750P-AF, however Ultra X4 500 W provides higher efficiency and comes with a fully modular cabling system (besides being limited to 500 W, of course) and it is on the same price range as 500 W units from Zalman and Enermax.

This way Ultra X4 500 W is one of the best 500 W units around – until someone releases an 80 Plus Silver or Gold 500 W unit.

Originally at http://www.hardwaresecrets.com/article/Ultra-X4-500-W-Power-Supply-Review/867


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