Seasonic X Series 760W Power Supply Review

paulktreg - 2010-12-02 13:41:03 in Power Supplies
Category: Power Supplies
Reviewed by: paulktreg   
Reviewed on: January 19, 2011
Price: $182.00

Introduction:

Sea Sonic Electronics started life back in 1975 as a manufacturer of electronic test equipment and entered the PC power supply market in 1980. It wasn’t until 2003 that Sea Sonic launched retail power supplies under their own brand name and currently offers a wide range of power supplies for the PC enthusiast, server and industrial market. Sea Sonic still offer bulk power supplies for the PC manufacturing market but it’s the retail units, Sea Sonic branded, that the PC enthusiasts will no doubt be more familiar. The retail ATX power supply product range isn’t extensive but Sea Sonic power supplies have, on the whole a great reputation, the M12D immediately springs to mind.

This is the first Sea Sonic, or more commonly Seasonic, power supply I have tested for OCC and it’s one of their latest, the X-Series 760W. According to the Seasonic website it’s the first full modular multi-output ATX, high wattage power supply that has obtained 80 Plus Gold certification so let’s have a look at it and see how well it performs.

Closer Look:

The Seasonic X-Series 760W power supply box is largely based on a black and gold theme with a splash of color used on some of the illustrations. The top of the box is satin black with a gloss honeycombed pattern watermark, mimicking the power supply exhaust grill no doubt, and carries a photograph of the power supply along with the Seasonic trademark, power supply wattage and an 80 Plus Gold logo. The bottom of the box is used to explain some of the technology and features of the Seasonic X-Series 760W power supply.

 

 

 

 

 

 

 

 

The front face of the box pretty much repeats the information on the top of the box with the addition of an Nvidia SLI Ready logo. The opposite face shows the main features, white text on a gold background, in several different languages.

 

 

The side panels show a photograph of the power supply modular cable connector panel, specification table, connector types and quantities, technical data and agency approval logos.

 

 

Lift the lid and the user manual sits on top of the power supply foam protection with the modular cable bag tucked neatly down the side. Remove the foam lid and the power supply sits underneath in a black felt drawstring bag.

 

 

Bagged power supply along with the full box contents which includes the modular cable bag, user manual, power cord, mounting screws and a selection of standard and Velcro cable ties.

 

 

The Seasonic X-Series 760W power supply is well packaged with a good set of accessories so let’s move on and have a closer look.

Closer Look:

The Seasonic X-Series 760W is nicely finished in a black, slightly textured, satin paint which is great at hiding fingerprints and scratches. (There is a cardboard sash around the power supply, not shown in the photograph, with a note reminding the user that the cooling fan will not run until approximately 20% of maximum rated power is attained).

 

 

 

 

 

 

 

 

 

 

 

 

The rear of the unit showing the hexagonal holed exhaust grill, IEC mains input connector, on/off switch and gold Seasonic logo. The front face showing the modular cable connector panel with all the connectors labeled. There is a little note on the bottom right of the panel to remind the user that the cooling fan is temperature controlled and will operate only when needed.

 

 

A comprehensive specification label occupies one side of the power supply with an X-Series “Go for Gold” logo on the other.

 

 

The black cooling fan is covered with a hexagonal holed grill that is pressed from the case body which does away with the need for a separate wire grill.

 

 

The Seasonic X-Series 760W is a fully modular unit with a comprehensive set of well made and fully braided modular cables.

 

The cooling fan is mounted to the lid of the power supply rather than the usual top and side panel type construction. The 120mm fan is a high quality San Ace 120 by Sanyo Denki, model 9S1212F404. The layout of the printed circuit board is neat and tidy but what immediately stands out is the heat sink size or lack off; a good indicator of high efficiency, we will see.

 

 

The transient filtering on the Seasonic X-Series 760W looks particularly good with the use of a filtered mains input connector in addition to the usual components on the printed circuit board. The modular cable connector board is used for the 3V3 and 5V regulators to improve efficiency, more on this later.

 

 

There’s little doubt that the Seasonic X-Series 760W power supply build quality is very high; it shouts quality as soon as you pick it up if you know what I mean. The electrolytic capacitors are a mixture of high quality Nippon Chemi-Con 105°C rated devices and solid aluminium capacitors but how well does it perform? It’s all very well having a great set of accessories, good build quality, great packaging but how does it perform? Let’s find out.

Specification:

 

Review Sample: Seasonic X-Series 760W Power Supply, Part Number: SS-760KM Active PFC F3 .

 

Ratings Table:

 

 

 

 

 

 

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) Power Supply Specification Table
AC Input
90 - 264V     9 – 4.5A     50-60Hz
DC Output
+3V3
+5V
+12V
-12V
+5VSB
Maximum Load
25A
25A
63A
0.5A
3A
Maximum Combined Wattage
125W
756W
6W
15W
750W

 

System Protection:

OPP, OVP, UVP, SCP, OCP & OTP.

 

Safety & Agency Approvals:

cTUVus, TUV, CCC, Gost-R, UkrTEST, CB, BSMI, CE, FCC, C-Tick, WEEE & RoHS.

 

Power Supply Physical Characteristics:

 

Seasonic X-Series 760W Power Supply Physical Characteristics
Weight
Length
Width
Height
4.0lbs/1.8kg
6.3in/160mm
5.9in/150mm
3.4in/86mm

 

Power Supply Connectors:

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) Power Supply Connectors
Connector Type
Qty
Motherboard 20/24 Pin
1
EPS12V 8 Pin
1
EPS12V/ATX12V 4+4 Pin
1
PCI-E 6+2 Pin
4
SATA Power 15 Pin
8
Peripheral 4 Pin
8
FDD 4 Pin
2

 

Power Supply Cable Lengths:

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) Power Supply Cable Set
Cable Type
Cable Length/Connector Spacing’s
Qty
Modular
PSU > 23" > Motherboard 20/24 Pin
1
Modular
PSU > 25" > EPS12V 8 Pin
1
Modular
PSU > 25" > ATX12V/EPS12V 4+4 Pin
1
Modular
PSU > 25" > 2 x PCI-E 6+2 Pin
2
Modular
PSU > 22" > SATA > 6" > SATA > 6" > SATA
2
Modular
PSU > 18" > SATA > 6" > SATA
1
Modular
PSU > 22" > Peripheral > 6" > Peripheral > 6" > Peripheral
2
Modular
PSU > 18" > Peripheral > 6" > Peripheral
1
Adapter
Peripheral > 6" > 2 x FDD
1

 

Features:

Exactly as printed in the user manual.

 

 

 

All information courtesy of Seasonic USA @ http://www.seasonicusa.com/NEW_X-series_560-660-760-850.htm

Testing:

For more information on how we test our power supplies, please browse our testing methodology.

 

Short Circuit Protection:

I short circuited the 3V3, 5V0 and the 12V rail(s) in turn. The power supply did shut down, and once the short was removed and the unit switched off for at least one second, resumed normal operation. Although listed here at the beginning of the testing section, I tend to leave this test until the very end, in case it doesn't quite go to plan.

 

DC Output Voltage Load Regulation:

 

Mains Input Voltage 110VAC

 

 

 

 

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 110VAC/50Hz
PSU DC Rail
Measured Voltage(V)
3V3
3.40
5V0
5.05
+12V
12.24
-12V
11.89
5VSB
5.11
Total PSU DC Loading = 0W (0% of Rated Maximum Output Power)

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 110VAC/50Hz
PSU
DC Rail
Rail Loading Amps (A)
Rail Loading Watts (W)
Measured Voltage (V)
ATX12V V2.2 Limits (V)
Pass/Fail
+3V3
3.20
10.78
3.37
3.135 – 3.465
Pass
+5V
4.78
24.04
5.03
4.75 – 5.25
Pass
+12V
7.73
94.38
12.21
11. – 12.6
Pass
-12V
0.35
4.15
11.86
10.8 – 13.2
Pass
+5VSB
2.13
10.46
4.91
4.75 – 5.25
Pass
Total PSU DC Loading = 144W (19% of Rated Maximum Output Power)

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 110VAC/50Hz
PSU
DC Rail
Rail Loading Amps (A)
Rail Loading Watts (W)
Measured Voltage (V)
ATX12V V2.2 Limits (V)
Pass/Fail
+3V3
3.26
10.99
3.37
3.135 – 3.465
Pass
+5V
4.80
24.10
5.02
4.75 – 5.25
Pass
+12V
27.04
329.90
12.20
11. – 12.6
Pass
-12V
0.35
4.15
11.85
10.8 – 13.2
Pass
+5VSB
2.12
10.37
4.89
4.75 – 5.25
Pass
Total PSU DC Loading = 379W (50% of Rated Maximum Output Power)

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 110VAC/50Hz
PSU
DC Rail
Rail Loading Amps (A)
Rail Loading Watts (W)
Measured Voltage (V)
ATX12V V2.2 Limits (V)
Pass/Fail
+3V3
8.35
27.80
3.33
3.135 – 3.465
Pass
+5V
9.74
48.41
4.97
4.75 – 5.25
Pass
+12V
58.27
706.81
12.13
11. – 12.6
Pass
-12V
0.37
4.41
11.92
10.8 – 13.2
Pass
+5VSB
2.12
10.22
4.82
4.75 – 5.25
Pass
Total PSU DC Loading = 798W (105% of Rated Maximum Output Power)

 

Mains Input Voltage 230VAC

 

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 230VAC/50Hz
PSU DC Rail
Measured Voltage(V)
3V3
3.40
5V0
5.08
+12V
12.24
-12V
11.89
5VSB
5.11
Total PSU DC Loading = 0W (0% of Rated Maximum Output Power)

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 230VAC/50Hz
PSU
DC Rail
Rail Loading Amps (A)
Rail Loading Watts (W)
Measured Voltage (V)
ATX12V V2.2 Limits (V)
Pass/Fail
+3V3
3.20
10.78
3.37
3.135 – 3.465
Pass
+5V
4.79
24.09
5.03
4.75 – 5.25
Pass
+12V
7.71
94.14
12.21
11. – 12.6
Pass
-12V
0.35
4.15
11.85
10.8 – 13.2
Pass
+5VSB
2.14
10.57
4.94
4.75 – 5.25
Pass
Total PSU DC Loading = 144W (19% of Rated Maximum Output Power)

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 230VAC/50Hz
PSU
DC Rail
Rail Loading Amps (A)
Rail Loading Watts (W)
Measured Voltage (V)
ATX12V V2.2 Limits (V)
Pass/Fail
+3V3
3.25
10.95
3.37
3.135 – 3.465
Pass
+5V
4.80
24.14
5.03
4.75 – 5.25
Pass
+12V
27.14
331.11
12.20
11. – 12.6
Pass
-12V
0.36
4.27
11.87
10.8 – 13.2
Pass
+5VSB
2.12
10.37
4.89
4.75 – 5.25
Pass
Total PSU DC Loading = 381W (50% of Rated Maximum Output Power)

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) DC Output Voltage Load Regulation
Supply = 230VAC/50Hz
PSU
DC Rail
Rail Loading Amps (A)
Rail Loading Watts (W)
Measured Voltage (V)
ATX12V V2.2 Limits (V)
Pass/Fail
+3V3
8.51
28.34
3.33
3.135 – 3.465
Pass
+5V
9.72
48.31
4.97
4.75 – 5.25
Pass
+12V
58.27
706.23
12.12
11. – 12.6
Pass
-12V
0.37
4.41
11.92
10.8 – 13.2
Pass
+5VSB
2.13
10.50
4.93
4.75 – 5.25
Pass
Total PSU DC Loading = 798W (105% of Rated Maximum Output Power)

 

The Seasonic X-Series 760W power supply produced a solid set of results in this section. The DC output voltage regulation is on a par with other power supplies in its class as shown by the virtually straight line graphs and drops of no more than 100mV on all the rails from zero to full load.

Testing:

Efficiency and Power Factor:

 

 

 

 

 

 

 

 

 

 

 

I think this is the first time a power supply as produced efficiency levels that meet its certified 80 Plus level following the OCC testing methodology. It’s not usually a defect in the power supply but more my inability to exactly follow the testing protocol used by the 80 Plus organisation which leads to lower, but not by much, measured efficiency levels. The Seasonic X-Series 760W produced efficiency levels of 87%, 90% and 87% whilst powered from 110VAC that exactly meet the 80 Plus Gold requirements. Power factor levels are fine but then again they usually are with a basic requirement of 0.9 or better at 50% loading.

 

 

The Seasonic X-Series 760W power supply excels even further when powered from 230VAC with efficiency levels of 89%, 92% and 89% with power factor levels once again proving to be well within the required levels.

The Seasonic X-Series 760W is one of the most efficient power supplies I’ve tested for OCC so let’s move on and have a look at the DC quality.

 

AC Ripple On DC Outputs:

 

I have consistently found the AC ripple levels on the DC rails to be more or less equal with an 110VAC or 230VAC mains supply. The results given below are for 230VAC only but I will continue to check the levels at 110VAC during testing and publish them below if there are any significant differences.

 

AC ripple/noise on the +3V3 rail at 230VAC

Oscilloscope settings: Amplitude = 5mv/div, Timebase = 10uS/div

 

AC ripple/noise on the +5V0 rail at 230VAC

Oscilloscope settings: Amplitude = 5mv/div, Timebase = 10uS/div

 

AC ripple/noise on the +12V rail at 230VAC

Oscilloscope settings: Amplitude = 5mv/div, Timebase = 10uS/div

 

AC ripple/noise on the -12V rail at 230VAC

Oscilloscope settings: Amplitude = 5mv/div, Timebase = 10uS/div

 

AC ripple/noise on the +5VSB rail at 230VAC

Oscilloscope settings: Amplitude = 5mv/div, Timebase = 10uS/div

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) AC Ripple/Noise
Supply = 230VAC/50Hz DC Loading = 798W
DC Rail
+3V3
+5V0
+12V
-12V0
+5VSB
ATX12 Max (mV p-p)
50
50
120
120
50
Ripple (mV p-p)
25
25
25
30
25
Pass/Fail
Pass
Pass
Pass
Pass
Pass

The noise/ripple levels on the DC rails of the Seasonic X-Series 760W power supply are well within the requirements laid down by the ATX12V V2.2 specification. I’ve seen lower levels on other power supplies in this class but they are perfectly acceptable and only 25mV on the 12V rail is still very good. No problems here so let’s move on.

Testing:

Temperature, Noise Levels and Fan Speeds:

I am not going to give a pass or fail in this section, as the ATX12V V2.2 does not really have any references on which to base a decision.

Temperatures are purely for information only, as there are too many variables involved when installed in a case, which, by the way, it wasn't. Ambient temperature, processor cooling efficiency and case cooling fans all play their part on the temperature of the air entering the power supply, and consequently the temperature of the air leaving it. No valid conclusions can be made from this test.

 

Seasonic X-Series 760W (SS-760KM Active PFC F3) Temperature & Fan Speeds
Supply = 110VAC/230VAC
DC Loading(W)
Temp In (°C)
Temp Out (°C)
Δ Temp (°C)
Fan Speed (RPM)
0
N/A
N/A
N/A
0/0
144/144
N/A
N/A
N/A
0/0
379/381
24.4/24.6
36.4/33.7
12.0/9.1
556/551
798/798
24.9/25.0
36.6/33.3
11.7/8.3
1835/1830

The Seasonic X-Series 760W power supply cooling fan didn’t really kick in until it came time to delivery half its rated power of approximately 380W. The cooling fan did spring into life when delivering 144W but it was only for short bursts of a few seconds at a speed of 500 RPM or so and only once or twice a minute. It was impossible to gain any real temperature data with this sort of fan behaviour so it’s not really zero fan operation at 144W it’s more like on for two seconds, off for thirty and that’s a little difficult to quantify. There is no load test between 20% and 50% following the OCC power supply testing methodology, so it’s difficult to say at what point the cooling fan runs constantly but it’s certainly very quiet when the power supply delivers half its rated power. The fan noise does however increase noticeably when it hits 1800 RPM at full load but this is to be expected and it’s on a par with other power supplies in this class.

Conclusion:

 

Price Per the Watt:

Power Supply Seasonic X-Series 760W at $182.00 = $0.24/Watt (12-2010)

 

The Seasonic X-Series 760W power supply comes well packaged with a great set of accessories. I don’t know why, but it just oozes quality when you pick it up and on further inspection the build quality is confirmed. I’m not a fan of fully modular power supplies, I can’t see the point of a modular motherboard cable for example, but it works here and works very well.

The Seasonic X-Series 760W power supply performed flawlessly throughout testing and is without doubt one of better power supplies I’ve tested for OCC. The DC voltage load regulation and DC quality is on a par with other power supplies in its class but it really excelled in the efficiency stakes and produced some of the best figures I’ve seen with a maximum of 90% on 110VAC and 92% on 230VAC.

If you are in need of a power supply that will stay cool and quiet whilst surfing or performing simple office tasks with the knowledge that the power is there should you want to fire up your favourite game on your dual graphics card setup then the Seasonic X-Series 760W is certainly worthy of your consideration. It’s a little on the expensive side but the old adage you get what you pay for certainly applies. The Seasonic X-Series 760W power supply looks good, performs very well and I have no hesitation in awarding it the OCC Editors Choice award.

 

Pros:

 

Cons: