XFX PRO 650 W XXX Edition Power Supply Review
By Gabriel Torres on July 27, 2012


Introduction

Hardware Secrets Golden Award

The PRO “XXX Edition” is a new power supply series from XFX with a modular cabling system and the 80 Plus Bronze certification. Models from XFX without a modular cabling system are called “Core Edition.” Let’s see how the 650 W model fared on our tests.

Power supplies from XFX are manufactured by Seasonic. The PRO 650 W XXX Edition is a relabeled Seasonic M12II Bronze 650 W (SS-650AM). Internally, this power supply is slightly different from the PRO 650 W “Core Edition,” and we will point out the differences throughout the review.

XFX Pro 650w XXX Edition
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Figure 1: XFX PRO 650 W XXX Edition power supply

XFX Pro 650w XXX Edition
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Figure 2: XFX PRO 650 W XXX Edition power supply

The XFX PRO 650 W XXX Edition is 6.3” (160 mm) deep, using a 135 mm ball bearing fan on its bottom (ADDA ADN512UB-A90).

XFX Pro 650w XXX Edition
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Figure 3: Fan

The reviewed power supply has a modular cabling system with six connectors: two for video cards or ATX12V/EPS12Vconnectors and four for SATA or peripheral power cables. The main motherboard cable, the ATX12V/EPS12V, and one video card cable are permanently attached to the power supply, and they are protected with nylon sleeves that come from inside the unit. This power supply comes with the following cables:

All wires are 18 AWG, which is the minimum recommended gauge. This is a good configuration for a 650 W power supply, allowing you to install two high-end video cards that require two auxiliary power connectors each without the need for adapters.

XFX Pro 650w XXX Edition
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Figure 4: Cables

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

A Look Inside the XFX PRO 650 W XXX Edition

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.

XFX Pro 650w XXX Edition
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Figure 5: Top view

XFX Pro 650w XXX Edition
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Figure 6: Front quarter view

XFX Pro 650w XXX Edition
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Figure 7: Rear quarter view

XFX Pro 650w XXX Edition
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Figure 8: The printed circuit board

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 and one ferrite coil more than the minimum required, and with two additional Y capacitors after the rectifying bridges.

XFX Pro 650w XXX Edition
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Figure 9: Transient filtering stage (part 1)

XFX Pro 650w XXX Edition
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Figure 10: Transient filtering stage (part 2)

On the next page, we will have a more detailed discussion about the components used in the XFX PRO 650 W XXX Edition.

Primary Analysis

On this page we will take an in-depth look at the primary stage of the XFX PRO 650 W XXX Edition. For a better understanding, please read our “Anatomy of Switching Power Supplies” tutorial.

This power supply uses two GBU606 rectifying bridges connected in parallel and attached to an individual heatsink. Each bridge supports up to 6 A at 100° C. So, in theory, you would be able to pull up to 1,380 W from a 115 V power grid. Assuming 80% efficiency, the bridges would allow this unit to deliver up to 1,104 W without burning themselves out. Of course, we are only talking about these particular components. The real limit will depend on all the components combined in this power supply.

XFX Pro 650w XXX Edition
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Figure 11: Rectifying bridges

The active PFC circuit uses three FDP18N50 MOSFETs, each supporting up to 18 A at 25° C or 10.8 A at 100° C in continuous mode (see the difference temperature makes) or 72 A at 25° C in pulse mode. These transistors present a maximum 265 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 PRO 650 W Core Edition uses two 20 A transistors here.

XFX Pro 650w XXX Edition
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Figure 12: Active PFC transistors

The output of the active PFC circuit is filtered by two 220 µF x 400 V Japanese electrolytic capacitors, from Rubycon, labeled at 105° C. These capacitors are connected in parallel and are the equivalent of a single 440 µF x 400 V capacitor.

XFX Pro 650w XXX Edition
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Figure 13: Capacitors

In the switching section, another two FDP18N50 MOSFETs are employed using the traditional two-transistor forward configuration. The specifications for these transistors were already discussed above. The PRO 650 W Core Edition uses two 20 A transistors here.

XFX Pro 650w XXX Edition
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Figure 14: One of the switching transistors and the active PFC diode

The primary is managed by a CM6802 active PFC/PWM combo controller.  

XFX Pro 650w XXX Edition
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Figure 15: Active PFC/PWM combo controller

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

Secondary Analysis

The XFX PRO 650 W XXX Edition 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. This design is used to increase efficiency.

The maximum theoretical current that 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. As an exercise, we can assume a duty cycle of 30 percent.

The +12 V output uses four SBR30A50CT Schottky rectifiers, each supporting up to 30 A (15 A per internal diode at 110° C with a 0.55 V maximum voltage drop). From the eight available diodes (two per rectifier pack), three are used in the direct rectification and five are used in the “freewheeling” part of the rectification. The PRO 650 W Core Edition uses the same rectifiers, with the same configuration.

XFX Pro 650w XXX Edition
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Figure 16: The +12 V rectifiers

As explained, the +5 V and +3.3 V outputs are produced by two DC-DC converters, which are located on the same daughterboard and controlled by the same integrated circuit, an APW7159. The +5 V converter uses four IPD060N03L G MOSFETs, while the +3.3 V converter uses three of them. Each of these transistors supports up to 50 A at 100° C in continuous mode or up to 350 A at 25° C in pulse mode, with a maximum RDS(on) of 6 mΩ. The PRO 650 W Core Edition uses different transistors here.

XFX Pro 650w XXX Edition
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Figure 17: The DC-DC converters

XFX Pro 650w XXX Edition
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Figure 18: The DC-DC converters

This power supply uses a PS223 monitoring integrated circuit, which supports over voltage (OVP), under voltage (UVP), over current (OCP), and over temperature (OTP) protections. This integrated circuit has two +12 V OCP channels, but the manufacturer decided to use only one of them, resulting in this unit having a single +12 V rail.

 

XFX Pro 650w XXX Edition
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Figure 19: Monitoring circuit

The electrolytic capacitors that filter the outputs are also Japanese, from Chemi-Con, and labeled at 105° C, as usual. See Figure 20.

XFX Pro 650w XXX Edition
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Figure 20: Capacitors

Power Distribution

In Figure 21, you can see the power supply label containing all the power specs.

XFX Pro 650w XXX Edition
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Figure 21: Power supply label

As you can see, this power supply 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.

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

5 A (60 W)

10 A (120 W)

14.5 A (174 W)

19 A (228 W)

23.5 A (282 W)

+12VB

5 A (60 W)

10 A (120 W)

14 A (168 W)

19 A (228 W)

23.5 A (282 W)

+5 V

1 A (5 W)

2 A (10 W)

4 A (20 W)

6 A (30 W)

8 A (40 W)

+3.3 V

1 A (3.3 W)

2 A (6.6 W)

4 A (13.2 W)

6 A (19.8 W)

8 A (26.4 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

140.5 W

271.4 W

396.8 W

521.1 W

644.7 W

% Max Load

21.6%

41.8%

61.0%

80.2%

99.2%

Room Temp.

45.2° C

45.2° C

45.5° C

48.4° C

48.8° C

PSU Temp.

42.2° C

42.5° C

43.5° C

45.6° C

47.6° C

Voltage Regulation

Pass

Pass

Pass

Pass

Pass

Ripple and Noise

Pass

Pass

Pass

Pass

Pass

AC Power

168.4 W

318.5 W

468.6 W

625.0 W

789.0 W

Efficiency

83.4%

85.2%

84.7%

83.4%

81.7%

AC Voltage

115.9 V

114.5 V

113.1 V

111.7 V

110.2 V

Power Factor

0.985

0.99

0.995

0.997

0.997

Final Result

Pass

Pass

Pass

Pass

Pass

On our tests, the XFX PRO 650 W XXX Edition presented efficiency between 81.7% and 85.2%, virtually matching the 80 Plus Bronze certification, which promises a minimum efficiency of 82% at light (i.e., 20%) and full loads, and 85% at typical (i.e., 50%) load. The efficiency at full load was a tad below the 82% promised by the 80 Plus Bronze certification. Tests for the 80 Plus certification are conducted at 23° C, while we test power supplies between 45° C and 50° C, and efficiency drops as temperature increases.

While the +12 V and +5 V outputs always presented values closer to their nominal values than required (3% regulation), voltage regulation could be better at +3.3 V and +5VSB, as you can see in the table below. Nevertheless, all outputs were 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.

Input

Test 1

Test 2

Test 3

Test 4

Test 5

+12VA

≤ 3%

≤ 3%

≤ 3%

≤ 3%

≤ 3%

+12VB

≤ 3%

≤ 3%

≤ 3%

≤ 3%

≤ 3%

+5 V

≤ 3%

≤ 3%

≤ 3%

≤ 3%

≤ 3%

+3.3 V

≤ 3%

≤ 3%

≤ 3%

+3.16 V

+3.15 V

+5VSB

≤ 3%

≤ 3%

+4.83 V

+4.77 V

+4.77 V

-12 V

≤ 3%

≤ 3%

≤ 3%

≤ 3%

≤ 3%

Let’s discuss the ripple and noise levels on the next page.

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 XFX PRO 650 W XXX Edition provided extremely low ripple and noise levels.

Input

Test 1

Test 2

Test 3

Test 4

Test 5

+12VA

6.6 mV

8.6 mV

10.4 mV

12.8 mV

17.6 mV

+12VB

7.2 mV

9.2 mV

12.4 mV

14.2 mV

19.8 mV

+5 V

4.6 mV

5.0 mV

5.6 mV

6.4 mV

5.6 mV

+3.3 V

6.4 mV

7.8 mV

7.6 mV

8.8 mV

7.2 mV

+5VSB

8.0 mV

12.0 mV

20.0 mV

20.6 mV

12.8 mV

-12 V

13.2 mV

15.2 mV

17.6 mV

23.4 mV

27.4 mV

Below you can see the waveforms of the outputs during test five.

XFX Pro 650w XXX Edition
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Figure 22: +12VA input from load tester during test five at 644.7 W (17.6 mV)

XFX Pro 650w XXX Edition
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Figure 23: +12VB input from load tester during test five at 644.7 W (19.8 mV)

XFX Pro 650w XXX Edition
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Figure 24: +5V rail during test five at 644.7 W (5.6 mV)

XFX Pro 650w XXX Edition
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Figure 25: +3.3 V rail during test five at 644.7 W (7.2 mV)

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, since it shut down when we tried to pull more than what is listed below. During this test, the +3.3 V and +5VSB outputs presented voltages below their minimum allowed values, at +3.02 V and +4.74 V, respectively. Noise and ripple levels were still extremely low.

Input

Overload Test

+12VA

27 A (324 W)

+12VB

27 A (324 W)

+5 V

12 A (60 W)

+3.3 V

12 A (39.6 W)

+5VSB

3 A (15 W)

-12 V

0.5 A (6 W)

Total

756.4 W

% Max Load

116.4%

Room Temp.

49.4° C

PSU Temp.

49.5° C

AC Power

953.0 W

Efficiency

79.4%

AC Voltage

107.8 V

Power Factor

0.998

Main Specifications

The main specifications for the XFX PRO 650 W XXX Edition power supply include:

Conclusions

The XFX PRO 650 W XXX Edition is a good option for users looking for a power supply with the 80 Plus Bronze certification and modular cabling system. During our tests, efficiency was between 81.7% and 85.2%, noise and ripple levels were extremely low, and voltage regulation was satisfactory, even though it could be a little better on the +3.3 V and +5VSB lines at higher loads.

The PRO 650 W XXX Edition comes with a suggested price of USD 115, and we know that vendors usually offer power supplies below the suggested price. The non-modular model, the Core Edition, can be found today for USD 100 at Newegg.com, which is a terrific price tag. Our guess is that the XXX Edition will be offered around USD 5 or USD 10 above the Core Edition, so it will be up to you whether you want to pay a little more to get the modular cabling system.

By the way, internally, the XXX Edition and the Core Edition are not identical; we found small differences between the two, which we pointed out during our analysis of the primary of the reviewed power supply.

Originally at http://www.hardwaresecrets.com/article/XFX-PRO-650-W-XXX-Edition-Power-Supply-Review/1604


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