Corsair TX750 V2 750W & TX850 V2 850W Power Supply Review

paulktreg - 2011-03-29 11:17:43 in Power Supplies
Category: Power Supplies
Reviewed by: paulktreg   
Reviewed on: May 11, 2011
Price: $104.99 & $124.99

Introduction:

Founded as Corsair Microsystems in 1994, Corsair originally developed level 2 cache modules for OEMs. The release of Intel’s Pentium Pro processor with built in cache memory led Corsair to change their focus to DRAM modules. In 2002 Corsair began shipping memory modules specifically with the enthusiast in mind and today their high performance memory modules are probably the product that most enthusiasts associate with Corsair. Corsair has expanded its product range to now include power supplies, computer enclosures, processor coolers, solid state drives and other key system components.

The Corsair TX650, TX750 and TX850 power supplies have now been around for some time and I guess rather than discontinue what has proved to be a very successful product Corsair have decided to keep the model going a little longer and offer a few improvements with the V2 units. This time around OCC will take a look at two power supplies from the V2 range, the TX750V2 and TX850V2 power supplies and see just what improvements, if any, Corsair have made.

Closer Look:

The Corsair TX750V2 and TX850V2 boxes, with their yellow, black and white theme, are basically the same apart from model numbers and technical specification. The top face of the box shows a photograph of the cooling fan side of the power supply along with model number, Corsair logo and a small box in the top right hand corner showing it’s a V2 unit.

 

 

 

 

 

 

 

 

 

 

 

 

The bottom face of the box carries all the technical information including connector types and quantities (with photographs), the main features in five different languages, fan noise and efficiency graphs and specification tables.

 

 

The front face of the box shows the model number and V2, a further list of features in five different languages with a five year and 80 Plus Bronze logo.

 

 

Model number and V2, a photograph of the fan grill, more features, again in five different languages and conformance marks on the rear face.

 

 

The box comes with identical end panels that carry the same photograph as the rear face with the model number and V2 once again displayed.

 

 

Both power supplies are contained in a further brown cardboard box bearing the Corsair logo.

 

Lift the lid and both power supplies are identically packed. The instruction manual which covers the TX650, TX750 and TX850 sits on top of the foam protected power supply. Removal of the top foam cover reveals a black drawstring bag enclosed power supply with the cables, power cord and accessories neatly stored down the side.

 

 

The black drawstring bag with Corsair logo along with the full box contents which includes the power cord, user manual, cable ties, case badge and power supply mounting screws.

 

The Corsair TX750V2 and TX850V2 power supplies are well packaged with a good set of accessories so let’s move on and have a closer look.

Closer Look:

The black matt finish, used on the TX750V2 and TX850V2, always looks well in my opinion.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The rear of the power supply with its hexagonal holed exhaust grill, the usual IEC mains input connector and mains on/off switch and large clear model number sticker following the colour scheme of the packaging.

 

 

The cables are fully sleeved all the way into the power supply enclosure which always improves the appearance and the inclusion of a plastic grommet on the cable exit port prevents damage from sharp metal edges.

 

The side panel carries a large model number label with the Corsair name and logo. The label is inverted on the opposite face presumably so it’s visible the right way up no matter how the power supply is mounted and it’s visible through a side panel window.

 

 

The large black 140mm cooling fan is covered with a black wire grill bearing the Corsair logo at its center.

 

A comprehensive specification label on the top face includes a specification table, conformance marks, production test and serial number stickers with a short note on the dangers of opening up the unit.

 

 

The TX750V2 and TX850V2 have a fully captive cable set that is identical on both units.

 

The cooling fan used in the Corsair TX750V2 and TX850V2 is a good quality Yate Loon D14BH-12 rated at 12VDC 0.7A. A clear plastic baffle has been installed behind the fan on both power supplies to redirect the airflow for maximum cooling.

 

The printed circuit boards on both power supplies look identical but there are some differences. The values of two main smoothing capacitors in the top left hand corner are different on both boards and there are differences on the secondary side on the right hand side. These differences are good to see because it shows the board has actually been upgraded to cater for the higher power. The capacitors are all good quality Japanese branded components of the more welcome 105°C working temperature rating.

 

 

The Corsair TX750V2 and TX850V2 power supply build quality is excellent with good packaging and a nice set of accessories. What more could you ask for? Let’s move on and see how well it performs.

Specification:

 

Review Samples: Corsair TX750V2 Power Supply, Part Number CMPSU-750TXV2 & Corsair TX850V2 Power Supply, Part Number CMPSU-850TXV2

 

Ratings Tables:

 

 

 

 

 

 

 

 

 

 

 

 

Corsair TX750V2 (CMPSU-750TXV2) Power Supply Specification Table
AC Input
100-240VAC     10-5A     50-60Hz
DC Output
+3V3
+5V
+12V
-12V
+5VSB
Maximum Load
25A
25A
62A
0.5A
3A
Maximum Combined Wattage
150W
744W
6W
15W
750W

 

Corsair TX850V2 (CMPSU-850TXV2) Power Supply Specification Table
AC Input
100-240VAC     12-6A     50-60Hz
DC Output
+3V3
+5V
+12V
-12V
+5VSB
Maximum Load
25A
25A
70A
0.5A
3A
Maximum Combined Wattage
150W
840W
6W
15W
850W

 

System Protection:

No specific figures given for this section. See the feature list.

 

Safety & Agency Approvals:

 

Corsair TX750V2 & TX850V2 Power Supply Safety & Agency Approvals
FCC
FCC Rules Part 15 Class B
ICES
ICES-003
CE
EN55022:2006 + A1:2007 Class D, EN61000-3-2:2006 Class D, EN61000-3-3:1995 + A1:2001
 
+ A2:2005, EN55024:1998 +A1:2001 + A2:2003, IEC61000-4-2:1995 + A1:1998 + A2:2000,
 
IEC61000-4-3:2006, IEC61000-4-4:2004, IEC61000-4-5:2005, IEC6100-4-6:2003 + A1:2004
 
+ A2:2006, IEC61000-4-8:1993 + A1:2000, IEC61000-4-11:2004
cTUVus
UL 60950-1:2007, CAN/CSA C22.2 No.60950-1:2007
C-Tick
AS/NSZ CISPR 22:2006 Class B
TUV
EN60950-1
CB
IEC60950-1
CCC
GB4943, GB9254, GB17625.1
BSMI
CNS14336, CNS13438
GOST
R IEC60950-1-2005, R 51318.22-99, R 51318.24-99, R 51317.3.2-2006, R 51317.3.3-99
ROHS
2002/95/EC Restriction of Hazardous Substances Directive
WEEE
2002/96/EC Waste Electrical and Electronic Equipment Directive
ROHS
(China)
China Order No.39 Administration on the Control of Pollution Caused By Electronic
Information Products

 

Power Supply Physical Characteristics:

 

Corsair TX750V2 (CMPSU-750TXV2) Power Supply Physical Characteristics
Weight
Length
Width
Height
5.7lbs/2.6kg
6.3in/160mm
5.9in/150mm
3.4in/86mm

 

Corsair TX850V2 (CMPSU-850TXV2) Power Supply Physical Characteristics
Weight
Length
Width
Height
5.7lbs/2.6kg
6.3in/160mm
5.9in/150mm
3.4in/86mm

 

Power Supply Connectors:

 

Corsair TX750V2 & TX850V2 Power Supply Connectors
Connector Type
Qty
Motherboard 20/24 Pin
1
ATX12V/EPS12V 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:

 

Corsair TX750V2 & TX850V2 Power Supply Cable Set
Cable Type
Cable Length/Connector Spacing’s
Qty
Captive
PSU > 23.5" > Motherboard 20/24 Pin
1
Captive
PSU > 23.5" > ATX12V/EPS12V 4+4 Pin
1
Captive
PSU > 23.5" > PCI-E 6+2 Pin
4
Captive
PSU > 17" > SATA > 6" > SATA > 6" > SATA > 6" > SATA
2
Captive
PSU > 17" > Peripheral > 6" > Peripheral > 6" > Peripheral > 6" > Peripheral > 6" > FDD
2

 

Features:

 

 

 

All information courtesy of Corsair @ http://www.corsair.com/power-supplies/non-modular-psus/enthusiast-series-1.html

Testing:

TX750V2

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

 

 

 

 

 

 

 

 

 

 

Corsair TX750V2 DC Output Voltage Load Regulation
Supply = 110VAC/50Hz
PSU DC Rail
Measured Voltage(V)
3V3
3.36
5V0
5.07
+12V1
12.12
-12V
11.70
5VSB
5.08
Total PSU DC Loading = 0W (0% of Rated Maximum Output Power)

 

Corsair TX750V2 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
3.19
10.62
3.33
3.135 – 3.465
Pass
+5V
4.83
24.39
5.05
4.75 – 5.25
Pass
+12V1
7.63
92.25
12.09
11.4 – 12.6
Pass
-12V
0.34
3.94
11.66
10.8 – 13.2
Pass
+5VSB
2.12
10.39
4.90
4.75 – 5.25
Pass
Total PSU DC Loading = 142W (19% of Rated Maximum Output Power)

 

Corsair TX750V2 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
3.17
10.52
3.32
3.135 – 3.465
Pass
+5V
4.80
24.29
5.06
4.75 – 5.25
Pass
+12V1
26.35
318.57
12.09
11.4 – 12.6
Pass
-12V
0.34
3.98
11.70
10.8 – 13.2
Pass
+5VSB
2.12
10.43
4.92
4.75 – 5.25
Pass
Total PSU DC Loading = 368W (49% of Rated Maximum Output Power)

 

Corsair TX750V2 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
8.28
27.07
3.27
3.135 – 3.465
Pass
+5V
9.88
49.50
5.01
4.75 – 5.25
Pass
+12V1
53.82
648.00
12.04
11.4 – 12.6
Pass
-12V
0.34
3.99
11.75
10.8 – 13.2
Pass
+5VSB
2.11
10.25
4.86
4.75 – 5.25
Pass
Total PSU DC Loading = 739W (98.5% of Rated Maximum Output Power)

 

Mains Input Voltage 230VAC

 

 

Corsair TX750V2 DC Output Voltage Load Regulation
Supply = 230VAC/50Hz
PSU DC Rail
Measured Voltage(V)
3V3
3.36
5V0
5.07
+12V1
12.12
-12V
11.70
5VSB
5.08
Total PSU DC Loading = 0W (0% of Rated Maximum Output Power)

 

Corsair TX750V2 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
3.18
10.59
3.33
3.135 – 3.465
Pass
+5V
4.80
24.24
5.05
4.75 – 5.25
Pass
+12V1
7.64
92.37
12.09
11.4 – 12.6
Pass
-12V
0.34
3.98
11.70
10.8 – 13.2
Pass
+5VSB
2.12
10.43
4.92
4.75 – 5.25
Pass
Total PSU DC Loading = 142W (19% of Rated Maximum Output Power)

 

Corsair TX750V2 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
3.18
10.56
3.32
3.135 – 3.465
Pass
+5V
4.81
24.29
5.05
4.75 – 5.25
Pass
+12V1
26.52
320.63
12.09
11.4 – 12.6
Pass
-12V
0.34
3.98
11.70
10.8 – 13.2
Pass
+5VSB
2.12
10.39
4.90
4.75 – 5.25
Pass
Total PSU DC Loading = 370W (49% of Rated Maximum Output Power)

 

Corsair TX750V2 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
8.30
27.22
3.28
3.135 – 3.465
Pass
+5V
9.85
49.45
5.02
4.75 – 5.25
Pass
+12V1
54.36
654.49
12.04
11.4 – 12.6
Pass
-12V
0.34
3.99
11.74
10.8 – 13.2
Pass
+5VSB
2.11
10.27
4.87
4.75 – 5.25
Pass
Total PSU DC Loading = 745W (99% of Rated Maximum Output Power)

 

The Corsair TX750V2 power supply produced a great set of results in this section. The regulation was excellent with little voltage drop from zero to full load as shown by what are virtually straight lines on the graphs. No problems here so let's move on.

Testing:

TX750V2

Efficiency and Power Factor:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Corsair TX750V2 Efficiency & Power Factor
Supply = 110VAC/50Hz
DC Load (W)
0
142
368
739
DC Load As A Percent Of Max (%)
N/A
19
49
98.5
Efficiency (%)
N/A
80
85
80
Power Factor (PF)
0.87
0.99
0.99
0.99

Whilst not quite meeting the 80 Plus Bronze standard following the OCC testing methodolgy the Corsair TX750V2 did manage a maximum efficiency of 85% at approximately 50% DC load. The power factor is well within the required level of 0.9 which is usually the case.

 

 

Corsair TX750V2 Efficiency & Power Factor
Supply = 230VAC/50Hz
DC Load (W)
0
142
370
745
DC Load As A % Of Maximum
N/A
19
49
99
Efficiency
N/A
82.5
86
83.5
Power Factor (PF)
0.44
0.90
0.97
0.98

The Corsair TX750V2 produced efficiency levels that are a touch higher when supplied from 230VAC with a maximum level of 86%. Power factor levels are typical of a power supply in this class and maintained above 0.9 once the power supply was loaded at 142W.

Whilst these figures aren't spectacular the TX750V2 produced a set of results that are on a par with other power supplies in this class following the OCC testing methodology.

 

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

 

Corsair TX750V2 Power Supply AC Ripple/Noise
Supply = 230VAC/50Hz DC Loading = 745W
DC Rail
+3V3
+5V0
+12V
-12V0
+5VSB
ATX12 Max (mV p-p)
50
50
120
120
50
Ripple (mV p-p)
30
25
30
40
25
Pass/Fail
Pass
Pass
Pass
Pass
Pass

The TX750V2 produced a fairly average set of results in this section with the noise levels well within the requirements set down by the ATX12V V2.2 specification. A level of only 30mV on a heavily loaded +12V rail isn't too shoddy, is it? No real problems here so let's move on.

Testing:

TX750V2

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.

 

Corsair TX750V2 Power Supply 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
1231/1236
142/142
21.0/20.5
25.8/26.5
4.8/6.0
1232/1232
368/370
20.0/20.6
31.3/30.1
11.3/9.5
1237/1235
739/745
20.9/21.6
38.9/36.5
18.0/14.9
1958/2108

The Corsair TX750V2 kicked off with a fan starting speed of 1200 RPM which is a little higher than I've seen on other power supplies but with a quoted noise level of only 25dB it's very quiet. The full load speed of 2000 RPM is a different story and with a quoted noise level of 40dB it's certainly noticeable but not unbearable. Temperature differentials across the power supply are typical and there's nothing here out of the ordinary.

Testing:

TX850V2

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

 

 

 

 

 

 

 

 

Corsair TX850V2 DC Output Voltage Load Regulation
Supply = 110VAC/50Hz
PSU DC Rail
Measured Voltage(V)
3V3
3.36
5V0
5.07
+12V1
12.10
-12V
11.81
5VSB
5.10
Total PSU DC Loading = 0W (0% of Rated Maximum Output Power)

 

Corsair TX850V2 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
3.18
10.59
3.33
3.135 – 3.465
Pass
+5V
4.83
24.44
5.06
4.75 – 5.25
Pass
+12V1
10.13
122.27
12.07
11.4 – 12.6
Pass
-12V
0.35
4.12
11.77
10.8 – 13.2
Pass
+5VSB
2.11
10.42
4.94
4.75 – 5.25
Pass
Total PSU DC Loading = 172W (20% of Rated Maximum Output Power)

 

Corsair TX850V2 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
10.66
3.33
3.135 – 3.465
Pass
+5V
4.81
24.29
5.05
4.75 – 5.25
Pass
+12V1
31.80
383.83
12.07
11.4 – 12.6
Pass
-12V
0.35
4.13
11.81
10.8 – 13.2
Pass
+5VSB
2.11
10.40
4.93
4.75 – 5.25
Pass
Total PSU DC Loading = 433W (51% of Rated Maximum Output Power)

 

Corsair TX850V2 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
8.20
26.81
3.27
3.135 – 3.465
Pass
+5V
9.72
48.79
5.02
4.75 – 5.25
Pass
+12V1
61.29
736.70
12.02
11.4 – 12.6
Pass
-12V
0.35
4.15
11.86
10.8 – 13.2
Pass
+5VSB
2.11
10.25
4.86
4.75 – 5.25
Pass
Total PSU DC Loading = 827W (97% of Rated Maximum Output Power)

 

Mains Input Voltage 230VAC

 

 

Corsair TX850V2 DC Output Voltage Load Regulation
Supply = 230VAC/50Hz
PSU DC Rail
Measured Voltage(V)
3V3
3.36
5V0
5.07
+12V1
12.11
-12V
11.81
5VSB
5.10
Total PSU DC Loading = 0W (0% of Rated Maximum Output Power)

 

Corsair TX850V2 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
3.05
10.16
3.33
3.135 – 3.465
Pass
+5V
4.77
24.09
5.05
4.75 – 5.25
Pass
+12V1
10.08
121.67
12.07
11.4 – 12.6
Pass
-12V
0.35
4.13
11.80
10.8 – 13.2
Pass
+5VSB
2.11
10.40
4.93
4.75 – 5.25
Pass
Total PSU DC Loading = 170W (20% of Rated Maximum Output Power)

 

Corsair TX850V2 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
10.66
3.33
3.135 – 3.465
Pass
+5V
4.84
24.44
5.05
4.75 – 5.25
Pass
+12V1
31.86
384.55
12.07
11.4 – 12.6
Pass
-12V
0.35
4.13
11.81
10.8 – 13.2
Pass
+5VSB
2.11
10.38
4.92
4.75 – 5.25
Pass
Total PSU DC Loading = 434W (51% of Rated Maximum Output Power)

 

Corsair TX850V2 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
8.19
26.78
3.27
3.135 – 3.465
Pass
+5V
9.75
48.94
5.02
4.75 – 5.25
Pass
+12V1
60.99
733.10
12.02
11.4 – 12.6
Pass
-12V
0.35
4.15
11.86
10.8 – 13.2
Pass
+5VSB
2.11
10.27
4.87
4.75 – 5.25
Pass
Total PSU DC Loading = 823W (97% of Rated Maximum Output Power)

 

The Corsair TX850V2 power supply produced a great set of results in this section. The regulation was excellent with little voltage drop from zero to full load as shown by what are virtually straight lines on the graphs. No problems here so let's move on.

Testing:

TX850V2

Efficiency and Power Factor:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Corsair TX850V2 Efficiency & Power Factor
Supply = 110VAC/50Hz
DC Load (W)
0
172
433
827
DC Load As A % Of Maximum
N/A
20
51
97
Efficiency
N/A
81
85
80
Power Factor (PF)
0.82
0.98
0.99
0.99

Whilst not quite meeting the 80 Plus Bronze standard following the OCC testing methodolgy the Corsair TX850V2 did manage a maximum efficiency of 85% at approximately 50% DC load. The power factor is well within the required level of 0.9 which is usually the case.

 

 

Corsair TX850V2 Efficiency & Power Factor
Supply = 230VAC/50Hz
DC Load (W)
0
170
434
823
DC Load As A % Of Maximum
N/A
20
51
97
Efficiency
N/A
81
86
83
Power Factor (PF)
0.42
0.94
0.97
0.98

The Corsair TX850V2 produced efficiency levels that are a touch higher when supplied from 230VAC with a maximum level of 86%. Power factor levels are typical of a power supply in this class and maintained above 0.9 once the power supply was loaded at 170W.

Whilst these figures aren't spectacular the TX850V2 produced a set of results that are on a par with other power supplies in this class following the OCC testing methodology.

 

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

 

Corsair TX850V2 Power Supply AC Ripple/Noise
Supply = 230VAC/50Hz DC Loading = 795W
DC Rail
+3V3
+5V0
+12V
-12V0
+5VSB
ATX12 Max (mV p-p)
50
50
120
120
50
Ripple (mV p-p)
30
25
40
40
25
Pass/Fail
Pass
Pass
Pass
Pass
Pass

The TX850V2 produced a fairly average set of results in this section with the noise levels well within the requirements set down by the ATX12V V2.2 specification. A level of only 40mV on a heavily loaded +12V rail isn't too shoddy, is it? No real problems here so let's move on.

Testing:

TX850V2

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.

 

Corsair TX850V2 Power Supply 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
1188/1187
172/170
21.8/20.9
27.3/27.6
5.5/6.7
1190/1192
433/434
21.3/21.8
33.6/31.4
12.3/9.6
1197/1196
827/823
21.5/21.8
39.3/35.8
17.8/14.0
2197/2270

The Corsair TX850V2 kicked off with a fan starting speed of 1200 RPM which is a little higher than I've seen on other power supplies but with a quoted noise level of only 25dB it's very quiet. The full load speed of 2200 RPM is a different story and with a quoted noise level of 40dB it's certainly noticeable but not quite unbearable. Temperature differentials across the power supply are typical and there's nothing here out of the ordinary.

Conclusions:

 

Price Per the Watt:

Power Supply Corsair TX750 V2 750W at $104.99 = $0.14/Watt (05-2011)

Power Supply Corsair TX850 V2 850W at $124.99 = $0.15/Watt (05-2011)

 

So what's changed?

The second revision of the ever popular Corsair TX750 and TX850 power supply now offer 80 Plus Bronze efficiency as opposed to the standard 80 Plus certification of the original units. This in combination with far better noise/ripple on the DC rails and some improvements in the overall build quality, sleeved cables all the way into the power supply for example, do make for a better quality power supply. The Corsair TX750 V2 and TX850 V2 performed very well overall and to a very similar standard with the only difference of note being the slightly higher +12V ripple/noise levels on the 850W which is understandable given the higher rail loading. The efficiency levels although not quite hitting the required levels required by the 80 Plus Bronze certification following the OCC power supply testing methodology were still a respectable 85~86% at maximum with power factor levels causing no problems as usual.

The Corsair TX750 V2 750W and TX850 V2 850W are still very good power supplies but they now face stiff competition from the likes of the XFX Core Edition power supplies and I can't help but feel that Corsair haven't quite done enough second time around. They are priced slightly cheaper than the originally released units which is nice to see but 80 Plus Silver efficiency would have introduced a little space between them and some of the competition. The DC quality was good but the ripple/noise levels on the DC rails are still a little higher than other power supplies in this class and there is room for improvement.

The Corsair TX750 V2 750W and TX850 V2 850W are still very good power supplies and I'm sure they will still remain popular in the PC enthusiast community but I feel the performance could of been improved further second time around. The Corsiar V2 units did perform very well and are an improvement on their predecessors so they still come highly recommended and I have no hesitation in awarding them the OCC Silver award.

 

Pros:

 

Cons: