Corsair TX550M Gold Power Supply Review

Key Features

1. Low-Noise Operation: A 120mm rifle bearing fan creates less noise than traditional bearings, letting you focus more on the task at hand, whether it’s gaming or work.
2. Semi-Modular Cabling: Lets you connect the cables you need for a cleaner build with easy cable management, while dual EPS12V connectors ensure wide compatibility with modern graphics cards and motherboards.
3. 105°C-Rated Japanese Capacitors: For consistent and reliable power.
4. 80 PLUS Gold Certified: Guarantees up to 90% efficiency to use less AC power and produce less heat.
5. Modern Standby Compatible: Extremely fast wake-from-sleep times and better low-load efficiency.
6. Resonant LLC Topology with DC-to-DC Conversion: Provides clean, consistent power, reduces coil whine for quieter operation, and enables use of more energy efficient sleep states.
7. Compact Size: At just 140mm long, the TX-M Series is designed for great flexibility in build configurations.
8. Seven-Year Warranty: Your guarantee of reliable operation for years to come.

The Corsair TX550M ships in a brightly coloured yellow box, very similar in design to the CX650F I reviewed way back in October 2020.

The rear of the box showcases some of the main selling points, if you were browsing in a retail store. Does anyone still walk into a retail store to buy components? let us know in the comments below…

The 550W unit we are testing today ships with 6+2 pin PCIe connector to power a single graphics card. All of the lengths are perfectly suitable for a unit of this capacity.

The Corsair TX550-M is finished quite well for the price bracket, we like the fact Corsair have adopted a colour neutral design, with simple white accenting on the labels. The name of the power supply is listed along the sides of the chassis.

A 120mm fan is seen behind the vents on the top of the power supply. We will take a closer look at the fan when we open the unit later in the review.

One side of the power supply is home to the modular connectors across two small rows at the rear. The other side of the unit is home to the power connector, power switch and vented honeycomb panel.

The TX550M delivers close to 46A on the +12V rail which is adequate for a graphics card that would be installed in a system adopting a power supply of this capacity.

Corsair are using an NR120L (120mm) fan in this supply. Its a seven blade rifle bearing model with a 50,000 hour life rating. Rated 12V 0.22A. These are not a widely sold fan, but if you look hard you can find them online for around AUS$18 (approx. £9.80). There are no plastic covers on parts of the fan to force direct airflow downwards over specific areas of the unit.

Corsair have partnered up with Great Wall for this unit. It adopts a Resonant LLC topology with DC to DC conversion. It is very impressive to see Corsair using high grade Japanese 105C Rubycon capacitors in the primary stage – two rated 450V 270uF for a total of 520uF output capacity. There are several rows of heatsinks inside the unit to aid with cooling from the fan above. Soldering on the PCB is decent across the board.

The unit has OCP, OPP, OTP, OVP, SCP and UVP protection built into it.

Correctly testing power supplies is a complex procedure and KitGuru have configured a test bench which can deliver up to a 2,000 watt DC load. Due to public requests we changed our temperature settings increasing ambient temperatures by 10c (to 35c) in our environment to greater reflect warmer internal chassis conditions.

We use combinations of the following hardware:
• SunMoon SM-268
• CSI3710A Programmable DC load (+3.3V and +5V outputs)
• CSI3711A Programmable DC load (+12V1, +12V2, +12V3, and +12V4)
• Extech Power Analyzer
• Extech MultiMaster MM570 digital multimeter
• SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa)
• Digital oscilloscope (20M S/s with 12 Bit ADC)
• Variable Autotransformer, 1.4 KVA

We combine all +12V output for the results below.

DC Output Load Regulation
Combined DC Load	+3.3V		+5V		+12V		+5VSB
	A	V	A	V	A	V	A	V
110W	1.18	3.34	1.18	5.02	8.02	12.12	0.50	5.02
220W	2.06	3.34	2.07	5.02	16.13	12.11	0.50	5.02
340W	3.05	3.34	3.06	5.02	25.14	12.07	1.00	5.02
445W	4.12	3.33	4.06	5.01	33.25	12.02	1.50	5.02
550W	5.15	3.33	5.02	4.99	41.05	11.97	2.50	5.01

Corsair TX550M	Maximum Load
	642W

Load regulation is good across the output range. The power supply delivered 642 watts of power before it would shut down, safely.

Next we want to try Cross Loading. This basically means loads which are not balanced. If a PC for instance needs 500W on the +12V outputs but something like 30W via the combined 3.3V and +5V outputs then the voltage regulation can fluctuate badly.

Cross Load Testing	+3.3V		+5V		+12V		-12V		+5VSB
	A	V	A	V	A	V	A	V	A	V
493W	1.0	3.33	1.0	5.02	40.5	11.97	0.2	-12.02	0.50	5.02
153W	15.0	3.31	15.0	4.96	2.0	12.08	0.2	-12.01	0.50	5.02

The unit passed the Cross Load test without any concerns.

We then used an oscilloscope to measure AC ripple and noise present on the DC outputs. We set the oscilloscope time base to check for AC ripple at both high and low ends of the spectrum. ATX12V V2.2 specification for DC output ripple and noise is defined in the ATX 12V power supply design guide.

ATX12V Ver 2.2 Noise/Ripple Tolerance
Output	Ripple (mV p-p)
+3.3V	50
+5V	50
+12V1	120
+12V2	120
-12V	120
+5VSB	50

Obviously when measuring AC noise and ripple on the DC outputs the cleaner (less recorded) means we have a better end result. We measured this AC signal amplitude to see how closely the unit complied with the ATX standard.

AC Ripple (mV p-p)
DC Load	+3.3V	+5V	+12V	5VSB
110W	5	5	10	5
220W	5	5	15	5
340W	10	10	15	10
445W	10	15	20	10
550W	15	15	25	15

Noise suppression is good with the +3.3V and +5V rails peaking at 15mV. The +12V rail peaks at 25mV under full load conditions.

Efficiency (%)
110W	89.87
220W	91.91
340W	91.23
445W	90.88
550W	89.35

Efficiency is excellent, peaking at around 92% at around 50% load. At full load, this drops to around 89.35%. Solid results.

We take the issue of noise very seriously at KitGuru and this is why we have built a special home brew system as a reference point when we test noise levels of various components. Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on components we are testing. It also brings us slightly closer to industry standards, such as DIN 45635.

Today to test the Power Supply we have taken it into our acoustics room environment and have set our SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa) one meter away from the unit. We have no other fans running so we can effectively measure just the noise from the unit itself. That said, measuring lower than 28dBa proves very difficult, unless in strict laboratory conditions.

As this can be a little confusing for people, here are various dBa ratings in with real world situations to help describe the various levels.

KitGuru noise guide
10dBA – Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA – High Quality Computer fan
40dBA – A Bubbling Brook, or a Refrigerator
50dBA – Normal Conversation
60dBA – Laughter
70dBA – Vacuum Cleaner or Hairdryer
80dBA – City Traffic or a Garbage Disposal
90dBA – Motorcycle or Lawnmower
100dBA – MP3 Player at maximum output
110dBA – Orchestra
120dBA – Front row rock concert/Jet Engine
130dBA – Threshold of Pain
140dBA – Military Jet takeoff/Gunshot (close range)
160dBA – Instant Perforation of eardrum

Noise (dBA)
110W	<28.0
220W	<28.0
340W	30.2
445W	32.1
550W	33.4

The fan profile is not aggressive in this unit and under most load situations you can't really hear it. At full load it spins up and is clearly audible – however if you are running at a load close to 550W then opting for a 750w or 850W unit would be a better idea.

Temperature (c)
	Intake	Exhaust
110W	36	38
220W	37	41
340W	41	46
445W	45	52
550W	47	57

The overall efficiency of the unit and the good design ensures the unit is never running too hot, even under higher load situations.

Maximum load	Efficiency
642W	89.2

Pushing the power supply above its rated limits generates an efficiency level of 88.7%. This is not a viable ‘real world’ situation, but its interesting nonetheless.

The Corsair TX550M has proven to be a capable supply in our labs over the last week. These units target a mass enthusiast audience running a modest gaming system with a single graphics card. At a retail price around £70, it will prove affordable to a mass audience.

Technically, this unit is a no frills semi modular design which dealt with our suite of tests without any failures. It did not exhibit any concerning weakness under real world usage situations either, it was able to deliver over 600 watts of power before safety measures stepped in for a safe shutdown.

This is one of the quieter power supplies we have tested this year, and even at a constant 450 watts of power delivery when gaming, the fan did not make itself heard over a few system fans. If you need a constant 500 watt+ power delivery you really should be looking at a higher capacity power supply anyway.

The TX550M passed our demanding cross load test, and ripple suppression is also well within safety parameters with +3.3V and +5V peaking at 15mV. The +12V rail  peaked at 25mV when under full load. The units Load regulation proved solid as well throughout all our tests.

Currently the TX550M is available from Overclockers Uk for £69.95 inc vat HERE.

KitGuru says: If you are on a tight budget and are building a budget to mid level gaming system, the TX550M will certainly deliver high quality power. Reassuringly Corsair back the product up with a 7 year warranty.